Process for Making CGRP Receptor Antagonists

ABSTRACT

The invention encompasses a novel process for making piperidinone carboxamide indane and azainane derivatives, which are CGRP receptor antagonists useful for the treatment of migraine.

REFERENCE TO SEQUENCE LISTING

The official copy of the Sequence Listing is submitted concurrently withthe specification as an ASCII formatted text file via EFS-Web, with afile name of “23236USPSP-SEQLIST-09MAY2012”, a creation date of May 9,2012, and a size of 4,509 bytes. The Sequence Listing filed via EFS-Webis part of the Specification and is incorporated in its entirety byreference herein.

BACKGROUND OF THE INVENTION

This invention relates to a process for making piperidinone carboxamideindane and azainane derivatives, which are CGRP receptor antagonistsuseful for the treatment of migraine. This class of compounds isdescribed in U.S. patent application Ser. No. 13/293,166 filed Nov. 10,2011, Ser. No. 13/293,177 filed Nov. 10, 2011 and Ser. No. 13/293,186filed Nov. 10, 2011, and PCT International Application Nos.PCT/US11/60081 filed Nov. 10, 2011 and PCT/US11/60083 filed Nov. 10,2011.

CGRP (Calcitonin Gene-Related Peptide) is a naturally occurring 37-aminoacid peptide that is generated by tissue-specific alternate processingof calcitonin messenger RNA and is widely distributed in the central andperipheral nervous system. CGRP is localized predominantly in sensoryafferent and central neurons and mediates several biological actions,including vasodilation. CGRP is expressed in alpha- and beta-forms thatvary by one and three amino acids in the rat and human, respectively.CGRP-alpha and CGRP-beta display similar biological properties. Whenreleased from the cell, CGRP initiates its biological responses bybinding to specific cell surface receptors that are predominantlycoupled to the activation of adenylyl cyclase. CGRP receptors have beenidentified and pharmacologically evaluated in several tissues and cells,including those of brain, cardiovascular, endothelial, and smooth muscleorigin.

Based on pharmacological properties, these receptors are divided into atleast two subtypes, denoted CGRP₁ and CGRP₂. Human α-CGRP-(8-37), afragment of CGRP that lacks seven N-terminal amino acid residues, is aselective antagonist of CGRP₁, whereas the linear analogue of CGRP,diacetoamido methyl cysteine CGRP ([Cys(ACM)2,7]CGRP), is a selectiveagonist of CGRP₂. CGRP is a potent neuromodulator that has beenimplicated in the pathology of cerebrovascular disorders such asmigraine and cluster headache. In clinical studies, elevated levels ofCGRP in the jugular vein were found to occur during migraine attacks(Goadsby et al., Ann. Neurol., 1990, 28, 183-187), salivary levels ofCGRP are elevated in migraine subjects between attacks (Bellamy et al.,Headache, 2006, 46, 24-33), and CGRP itself has been shown to triggermigrainous headache (Lassen et al., Cephalalgia, 2002, 22, 54-61). Inclinical trials, the CGRP antagonist BIBN4096BS has been shown to beeffective in treating acute attacks of migraine (Olesen et al., NewEngl. J. Med., 2004, 350, 1104-1110) and was able to prevent headacheinduced by CGRP infusion in a control group (Petersen et al., Clin.Pharmacol. Ther., 2005, 77, 202-213).

CGRP-mediated activation of the trigeminovascular system may play a keyrole in migraine pathogenesis. Additionally, CGRP activates receptors onthe smooth muscle of intracranial vessels, leading to increasedvasodilation, which is thought to contribute to headache pain duringmigraine attacks (Lance, Headache Pathogenesis: Monoamines,Neuropeptides, Purines and Nitric Oxide, Lippincott-Raven Publishers,1997, 3-9). The middle meningeal artery, the principle artery in thedura mater, is innervated by sensory fibers from the trigeminal ganglionwhich contain several neuropeptides, including CGRP. Trigeminal ganglionstimulation in the cat resulted in increased levels of CGRP, and inhumans, activation of the trigeminal system caused facial flushing andincreased levels of CGRP in the external jugular vein (Goadsby et al.,Ann. Neurol., 1988, 23, 193-196). Electrical stimulation of the duramater in rats increased the diameter of the middle meningeal artery, aneffect that was blocked by prior administration of CGRP(8-37), a peptideCGRP antagonist (Williamson et al., Cephalalgia, 1997, 17, 525-531).Trigeminal ganglion stimulation increased facial blood flow in the rat,which was inhibited by CGRP(8-37) (Escott et al., Brain Res. 1995, 669,93-99). Electrical stimulation of the trigeminal ganglion in marmosetproduced an increase in facial blood flow that could be blocked by thenon-peptide CGRP antagonist BIBN4096BS (Doods et al., Br. J. Pharmacol.,2000, 129, 420-423). Thus the vascular effects of CGRP may beattenuated, prevented or reversed by a CGRP antagonist.

CGRP-mediated vasodilation of rat middle meningeal artery was shown tosensitize neurons of the trigeminal nucleus caudalis (Williamson et al.,The CGRP Family: Calcitonin Gene-Related Peptide (CGRP), Amylin, andAdrenomedullin, Landes Bioscience, 2000, 245-247). Similarly, distentionof dural blood vessels during migraine headache may sensitize trigeminalneurons. Some of the associated symptoms of migraine, includingextra-cranial pain and facial allodynia, may be the result of sensitizedtrigeminal neurons (Burstein et al., Ann. Neurol. 2000, 47, 614-624). ACGRP antagonist may be beneficial in attenuating, preventing orreversing the effects of neuronal sensitization.

The ability of the compounds to act as CGRP antagonists makes themuseful pharmacological agents for disorders that involve CGRP in humansand animals, but particularly in humans. Such disorders include migraineand cluster headache (Doods, Curr Opin Inves Drugs, 2001, 2 (9),1261-1268; Edvinsson et al., Cephalalgia, 1994, 14, 320-327); chronictension type headache (Ashina et al., Neurology, 2000, 14, 1335-1340);pain (Yu et al., Eur. J. Pharm., 1998, 347, 275-282); chronic pain(Hulsebosch et al., Pain, 2000, 86, 163-175); neurogenic inflammationand inflammatory pain (Holzer, Neurosci., 1988, 24, 739-768; Delay-Goyetet al., Acta Physiol. Scanda. 1992, 146, 537-538; Salmon et al., NatureNeurosci., 2001, 4(4), 357-358); eye pain (May et al. Cephalalgia, 2002,22, 195-196), tooth pain (Awawdeh et al., Int. Endocrin. J., 2002, 35,30-36), non-insulin dependent diabetes mellitus (Molina et al.,Diabetes, 1990, 39, 260-265); vascular disorders; inflammation (Zhang etal., Pain, 2001, 89, 265), arthritis, bronchial hyperreactivity, asthma,(Foster et al., Ann. NY Acad. Sci., 1992, 657, 397-404; Schini et al.,Am. J. Physiol., 1994, 267, H2483-H2490; Zheng et al., J. Virol., 1993,67, 5786-5791); shock, sepsis (Beer et al., Crit. Care Med., 2002, 30(8), 1794-1798); opiate withdrawal syndrome (Salmon et al., NatureNeurosci., 2001, 4(4), 357-358); morphine tolerance (Menard et al., J.Neurosci., 1996, 16 (7), 2342-2351); hot flashes in men and women (Chenet al., Lancet, 1993, 342, 49; Spetz et al., J. Urology, 2001, 166,1720-1723); allergic dermatitis (Wallengren, Contact Dermatitis, 2000,43 (3), 137-143); psoriasis; encephalitis, brain trauma, ischaemia,stroke, epilepsy, and neurodegenerative diseases (Rohrenbeck et al.,Neurobiol. of Disease 1999, 6, 15-34); skin diseases (Geppetti andHolzer, Eds., Neurogenic Inflammation, 1996, CRC Press, Boca Raton,Fla.), neurogenic cutaneous redness, skin rosaceousness and erythema;tinnitus (Herzog et al., J. Membrane Biology, 2002, 189(3), 225);inflammatory bowel disease, irritable bowel syndrome, (Hoffman et al.Scandinavian Journal of Gastroenterology, 2002, 37(4) 414-422) andcystitis. Of particular importance is the acute or prophylactictreatment of headache, including migraine and cluster headache.

The present invention describes a novel process for making piperidinonecarboxamide indane and azainane derivatives, which are CGRP receptorantagonists, having less steps and improved yields as compared toprevious synthetic methods for making these compounds.

SUMMARY OF THE INVENTION

The invention encompasses a novel process for making piperidinonecarboxamide indane and azainane derivatives, which are CGRP receptorantagonists useful for the treatment of migraine.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is described in connection with the appended drawings inwhich:

FIG. 1 is the X-ray powder diffraction (XRPD) pattern for(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemonohydrate;

FIG. 2 is the differential scanning calorimetry (DSC) thermogram for(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemonohydrate;

FIG. 3 is the XRPD pattern for(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidetrihydrate;

FIG. 4 is the DSC thermogram for(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidetrihydrate;

FIG. 5 is the XRPD of crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemonohydrate;

FIG. 6 is the DSC thermogram for crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemonohydrate;

FIG. 7 is the X-ray powder diffraction (XRPD) pattern for(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidetrihydrate;

FIG. 8 is the differential scanning calorimetry (DSC) thermogram for(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidetrihydrate;

FIG. 9 is the X-ray powder diffraction (XRPD) pattern for(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemethanol solvate;

FIG. 10 is the X-ray powder diffraction (XRPD) pattern for(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemethanol water solvate;

FIG. 11 is the XRPD of crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamideacetonitrile water solvate;

FIG. 12 is the XRPD of crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamideacetonitrile solvate;

FIG. 13 is the XRPD of X-ray Amorphous(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamide;

FIG. 14 is the X-ray powder diffraction (XRPD) pattern for(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamideacetonitrile solvate;

FIG. 15 is the XRPD of crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamideL-tartaric acid cocrystal;

FIG. 16 is the X-ray powder diffraction (XRPD) pattern for(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamideL-tartaric acid cocrystal; and

FIG. 17 is the X-ray powder diffraction (XRPD) pattern for a crystallineform of(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,5-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamide.

DETAILED DESCRIPTION OF THE INVENTION

The invention encompasses a process for making a compound of Formula I

or a pharmaceutically acceptable salt thereof, wherein:X is selected from —C(R³)═ or —N═, wherein R³ is hydrogen, F or CN;

Y is CH or N;

R¹ is selected from the group consisting of: C₁₋₄alkyl,cyclopropylmethyl, cyclobutylmethyl and[1-(trifluoromethyl)cyclopropyl]methyl, each of which is optionallysubstituted with one or more substituents as allowed by valenceindependently selected from the group consisting of: F and hydroxy; andR² is selected from hydrogen, methyl, F, Cl, or Br;comprising crystallizing the Formula A

in the presence of an arylaldehyde derivative and a first acid in afirst organic solvent to yield the compound of Formula B

optionally as a salt, and coupling the compound of Formula B with acompound of Formula C

or a salt thereof, under conditions for an amide bond formation betweenan acid and an amine to yield a compound of Formula I.

Conditions for an amide bond formation between an acid and amine includefor example reacting the compounds of Formulas B (after salt break) andC with an amide coupling reagent and optionally an additive and an acidand/or a base in a non-reactive solvent. Amide coupling reagentsinclude, for example, EDC, CDI, SOCl₂, (COCl)₂, DCC, T3P® (propanephosphonic acid anhydrie), DPPA, and the like. Additives include HOBT,HOAt, HATU, HOPO, and HOSu, pyridine, pyridine derivatives and the like.Appropriate bases include amines having formula N(R)₃, wherein each R isindependently hydrogen, alkyl and aryl, inorganic bases, such as sodiumhydroxide, lithium hydroxide, potassium hydroxide, sodium carbonate,sodium bicarbonate, potassium carbonate, potassium bicarbonate, lithiumcarbonate, lithium carbonate, cesium carbonate, potassium phosphate, andthe like. Conditions for an amide bond formation between an acid andamine also include utilizing acyl halides via mixed carbonic anhydrideintermediates. Examples include pivaloyl chloride, alkyl chloroformateplus a base. Further examples of peptide coupling reagents in organicsynthesis are well known in the art and described for example in Han, etal., Tetrahedron 60 (2004) 2447-2467.

In an embodiment, the compound of Formula B is coupled with a compoundof Formula C after salt break by reacting the reagents with an amidecoupling reagent and, optionally an amide coupling reagent additive, ina non-reactive solvent to yield a compound of Formula I. In anotherembodiment, the coupling regant is selected from EDC, HATU, T3P®, CDI,the amide coupling reagent additive is HOBT or HOPO and the non-reactivesolvent is an organic/aqueous mixture selected from DCM/water,iPAC/water, acetonitrile/water, acetone/water, iPA/water, EtOH/water,MeOH/water, acetone/water and THF/water.

In another embodiment of the invention, a salt of a compound of FormulaC is coupled to the compound of Formula B. Salts encompassed within theinvention include sodium hydroxide, potassium hydroxide, lithiumhydroxide, and corresponding carbonate and bicarbonate.

In another embodiment of the invention, the arylaldehyde derivative isselected from 2-hydroxybenzaldehyde, substituted 2-hydroxybenzaldehyde,such as 2-hydroxy-5-nitrobenzaldehyde and2-hydroxy-3,5-dichlorobenzaldehyde.

“First organic solvent” means any organic solvent appropriate for thereaction such as THF, Me-THF, MTBE and the like. The term “first acid”means for example HCl, MeSO₃H, H₂SO₄, p-toluenesulfonic acid and thelike. Selection of the appropriate solvent and acid is well within theskill of one having ordinary skill in the art.

Another embodiment of the invention encompasses the process describedabove further comprising making the compound of Formula A by reacting acompound of Formula D

wherein Z is an amine protecting group, with an electrophilic alkylatingagent that delivers a cationic R¹, such as R¹—OS(O)₂CF₃ or R¹—OS(O)₂F,in the presence of base and optionally an additive in a second organicsolvent to yield a compound of Formula E

and deprotecting the compound of Formula E to yield a compound ofFormula A.

Appropriate amine protecting groups that can be used in the presentinvention include for example, Boc, Cbz, ═C(Ph)₂, ═CHPh, and the like.Bases that may be used in the present invention include alkali metalbases, preferably lithium base, such as lithium tert-butoxide, lithiumtert-pentoxide. Optional additives are, for example, aprotic polarsolvents, such as DMPU, DMAc and DMF. The term second organic solventincludes THF, Me-THF, MTBE, and the like. The terms also includemixtures of solvents.

Deprotection can be carried out under acidic conditions, for exampleusing a second acid including but not limited to HCl, MeSO₃H, H₂SO₄,p-toluenesulfonic acid and the like, hydrogenation conditions or basicconditions as appropriate.

In another embodiment of the invention, Z is t-butyl-O—C(O)—, theelectrophilic alkylating agent is R¹—OS(O)₂CF₃ or R¹—OS(O)₂F,deprotection is effected by reacting the compound of Formula E with anacid, the lithium base is selected from LiOBut and LiOPent^(t), theadditive is an aprotic polar solvent, and the second organic solvent isselected from THF, Me-THF and MTBE. In another embodiment of theinvention, the second acid is selected from HCl, MeSO₃H, H₂SO₄,p-toluenesulfonic acid and benzenesulfonic acid.

The compound of Formula D described in the process above may be made byreacting a compound of Formula F

wherein R^(a) is C₁₋₆alkyl, with a transaminase enzyme having the aminoacid sequence of SEQ ID NO: 1 and the nucleotide sequence of SEQ ID NO:2 in an aqueous solvent mixture to yield a compound of Formula D. Underoptimized conditions, the compound of Formula F is reacted with thetransaminase enzyme of SEQ ID NO: 1 at a pH in the range of pH 10 to pH10.7 and an elevated temperature in the range of 45° C. to 60° C. Inanother embodiment, the reaction is run at a pH of about 10.5 and atemperature of about 55° C.

Another embodiment of the invention encompasses crystalline monohydratefree base of the compound having the structure

and having the following chemical name:(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemonohydrate.

X-ray powder diffraction studies are widely used to characterizemolecular structures, crystallinity, and polymorphism. The X-ray powderdiffraction patterns disclosed herein were generated on a PhilipsAnalytical X′Pert PRO X-ray Diffraction System with PW3040/60 console. APW3373/00 ceramic Cu LEF X-ray tube K-Alpha radiation was used as thesource.

FIG. 1 shows the X-ray powder diffraction pattern for crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemonohydrate. The monohydrate form is characterized by diffraction peakscorresponding to d-spacings as detailed in Table 1.

TABLE 1 Pos. [° Two Theta.] d-spacing [Å] Rel. Int. [%] 6.99 12.65 359.98 8.87 54 10.95 8.08 11 12.03 7.36 26 13.91 6.37 97 14.85 5.96 815.82 5.60 23 17.16 5.17 90 18.02 4.92 38 18.65 4.76 100 19.83 4.48 1420.12 4.41 18 20.47 4.34 30 21.20 4.19 8 22.44 3.96 87 24.27 3.67 1024.72 3.60 26 25.25 3.53 18 26.76 3.33 22 26.93 3.31 23 27.60 3.23 428.31 3.15 12 29.02 3.08 7 30.05 2.97 13 30.50 2.93 8 31.11 2.88 6 31.422.85 4 31.98 2.80 6 32.31 2.77 7 33.78 2.65 16 34.88 2.57 3

DSC data disclosed herein were acquired using TA Instruments DSC 2910 orequivalent instrumentation. A sample with a weight between 2 and 8 mgwas weighed into a pan and the pan was crimped and a pinhole placed inthe lid. This pan was placed in the sample position in the calorimetercell. An empty pan was placed in the reference position. The calorimetercell was closed and a flow of nitrogen is passed through the cell. Theheating program was set to heat the sample at a heating rate of 10°C./min to a temperature of approximately 300° C. When the run wascompleted, the data were analyzed using the DSC analysis program in thesystem software. The observed endotherms were integrated betweenbaseline temperature points that are above and below the temperaturerange over which the endotherm is observed. The data reported are theonset temperature, peak temperature and enthalpy.

FIG. 2 shows the DSC thermogram for crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemonohydrate. A broad endotherm with T_(onset)=143.9 C, T_(peak)=174.7 C,and ΔH=95.8 J/g is observed which is attributable to a dehydrationevent.

An embodiment of the invention encompasses crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemonohydrate having a DSC extrapolated onset melting temperature of about144° C. and a DSC peak melting temperature of about 175° C. Anotherembodiment of the invention encompasses crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemonohydrate having d-spacings determined by x-ray powder diffraction, CuK alpha, of about 12.7, 8.9, 8.1, 7.4, 6.4, 5.2, 4.9, 4.8 and 4.0angstroms.

FIG. 3 shows the X-ray powder diffraction pattern of crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidetrihydrate. The trihydrate form is characterized by diffraction peakscorresponding to d-spacings as detailed in Table 2.

TABLE 2 Pos. [° Two Theta.] d-spacing [Å] Rel. Int. [%] 6.27 14.09 117.43 11.90 72 9.44 9.37 4 10.12 8.74 21 11.66 7.59 9 12.31 7.19 52 12.746.95 7 13.60 6.51 100 14.25 6.22 34 14.98 5.91 49 15.25 5.81 45 16.715.30 22 17.36 5.11 37 18.18 4.88 63 18.67 4.75 36 19.43 4.57 52 20.084.42 13 20.47 4.34 33 21.58 4.12 43 22.65 3.93 28 23.36 3.81 50 24.453.64 12 25.40 3.51 23 25.94 3.43 24 26.90 3.31 12 28.30 3.15 12 28.533.13 13 29.09 3.07 17

FIG. 4 shows the DSC thermogram for crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidetrihydrate. A broad endotherm with extrapolated onset (T_(onset))=102.7°C., T_(peak)=136.1° C., and ΔH=240.2 J/g was observed that wasconsistent with a dehydration event. A small endotherm with extrapolatedonset (T_(onset))=160.4° C., T_(peak)=175.8° C., and ΔH=3.47 J/g wasobserved that was consistent with a melt/collapse of a dehydrated form.

Another embodiment of the invention encompasses crystalline monohydratefree base of the compound having the structure

FIG. 5 shows the X-ray powder diffraction pattern of crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemonohydrate. The monohydrate form is characterized by diffraction peakscorresponding to d-spacings as detailed in Table 3.

TABLE 3 Pos. [° Two Theta.] d-spacing [Å] Rel. Int. [%] 9.90 8.94 2911.10 7.97 6 12.16 7.28 17 14.06 6.30 100 14.94 5.93 12 15.72 5.64 3017.27 5.14 59 18.06 4.91 45 18.67 4.75 62 19.95 4.45 9 20.60 4.31 2821.24 4.18 19 22.42 3.97 60 22.98 3.87 21 23.50 3.79 9 24.60 3.62 925.08 3.55 17 25.61 3.48 10 27.05 3.30 27 27.53 3.24 6 28.48 3.13 728.91 3.09 3 29.36 3.04 3 30.27 2.95 7 30.63 2.92 5 31.12 2.87 6 32.342.77 8 33.92 2.64 9 34.38 2.61 5

FIG. 6 shows the DSC thermogram for crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemonohydrate. A melting endotherm coupled with dehydration was observedwith an extrapolated onset (T_(onset))=165.2° C., T_(peak)=171.1° C.,and ΔH=136.9 J/g.

An embodiment of the invention encompasses crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemonohydrate having a DSC extrapolated onset melting/dehydrationtemperature of about 165° C. and a DSC peak melting temperature of about171° C. Another embodiment of the invention encompasses crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemonohydrate having d-spacings determined by x-ray powder diffraction, CuK alpha, of about 8.9, 8.0, 7.3, 6.3, 5.9, 5.6, 5.1, 4.9, 4.8, 4.5 and4.3 angstroms.

Another embodiment of the invention encompasses crystalline trihydratefree base of the compound having the structure

and having the following chemical name:(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidetrihydrate.

FIG. 7 shows the X-ray powder diffraction pattern for crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidetrihydrate. The trihydrate form is characterized by diffraction peakscorresponding to d-spacings as detailed in Table 4.

TABLE 4 Pos. [° Two Theta.] d-spacing [Å] Rel. Int. [%] 6.34 13.95 307.32 12.07 5 9.36 9.45 5 10.10 8.76 38 11.52 7.68 8 12.11 7.31 42 12.816.91 12 13.44 6.59 70 14.00 6.33 19 14.29 6.20 33 14.79 5.99 27 15.295.79 49 15.63 5.67 8 16.59 5.34 31 17.27 5.13 34 18.13 4.89 91 18.434.81 54 19.25 4.61 68 20.41 4.35 96 21.26 4.18 26 21.64 4.11 77 22.343.98 43 22.65 3.93 33 23.39 3.80 100 24.18 3.68 27 24.44 3.64 17 24.903.58 16 25.04 3.56 35 25.44 3.50 46 25.67 3.47 38 26.74 3.33 46 27.223.28 14 27.52 3.24 22 28.31 3.15 18 28.96 3.08 25 29.76 3.00 11 30.192.96 22 31.10 2.88 12 32.15 2.78 14 32.41 2.76 9 32.96 2.72 16 33.712.66 9 34.04 2.63 8 35.98 2.50 20

FIG. 8 shows the DSC thermogram for crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidetrihydrate. A broad endotherm with extrapolated onset (T_(onset))=83.4°C., T_(peak)=115.0° C., and ΔH=108.6 J/g was observed that wasconsistent with a dehydration event. A small endotherm with extrapolatedonset (T_(onset))=166.6° C., T_(peak)=170.7° C., and ΔH=2.56 J/g wasobserved that was consistent with a melt/collapse of a dehydrated form.

Another embodiment of the invention encompasses crystalline methanolsolvate free base of the compound having the structure

and having the following chemical name:(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemethanol solvate.

FIG. 9 shows the X-ray powder diffraction pattern for crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemethanol solvate. The methanol solvate form is characterized bydiffraction peaks corresponding to d-spacings as detailed in Table 5.

TABLE 5 Pos. [° Two Theta.] d-spacing [Å] Rel. Int. [%] 6.89 12.83 139.67 9.15 10 10.69 8.28 12 11.71 7.56 6 13.82 6.41 45 14.51 6.10 5 15.475.73 27 16.82 5.27 47 17.72 5.00 19 18.29 4.85 55 19.76 4.49 100 20.354.36 18 20.93 4.24 10 21.97 4.05 89 22.54 3.94 10 23.06 3.86 5 23.713.75 11 24.30 3.66 17 24.81 3.59 10 26.24 3.40 10 26.61 3.35 28 27.583.23 6 29.43 3.04 10 30.54 2.93 5 31.05 2.88 6

Another embodiment of the invention encompasses crystallinemethanol-water mixed solvate free base of the compound having thestructure

and having the following chemical name:(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemethanol water solvate.

FIG. 10 shows the X-ray powder diffraction pattern for crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemethanol-water solvate The methanol-water mixed solvate form ischaracterized by diffraction peaks corresponding to d-spacings asdetailed in Table 6.

TABLE 6 Pos. [° Two Theta.] d-spacing [Å] Rel. Int. [%] 6.81 12.98 189.17 9.65 14 10.53 8.40 10 11.61 7.62 8 13.12 6.75 13 13.86 6.39 7014.76 6.00 36 16.23 5.46 7 16.72 5.30 100 17.33 5.12 32 17.51 5.06 7518.11 4.90 17 18.72 4.74 40 19.32 4.59 11 20.03 4.43 10 20.40 4.35 1320.84 4.26 57 21.26 4.18 84 21.97 4.05 21 22.91 3.88 15 23.30 3.82 2124.01 3.71 15 24.45 3.64 16 25.52 3.49 14 26.13 3.41 18 26.51 3.36 1426.83 3.32 19 28.02 3.18 16 28.55 3.13 20 29.27 3.05 7

Another embodiment of the invention encompasses crystalline acetonitrilewater solvate free base of the compound having the structure

FIG. 11 shows the X-ray powder diffraction pattern of crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamideacetronitrile water solvate The acetonitrile water solvate form ischaracterized by diffraction peaks corresponding to d-spacings asdetailed in Table 7.

TABLE 7 Pos. [° Two Theta.] d-spacing [Å] Rel. Int. [%] 4.30 20.53 1007.72 11.45 11 8.66 10.21 26 9.92 8.92 14 13.26 6.68 19 14.06 6.30 1414.95 5.93 20 15.12 5.86 24 15.48 5.72 23 15.96 5.55 21 16.71 5.31 2317.33 5.12 40 17.56 5.05 26 18.89 4.70 13 20.02 4.44 11 20.32 4.37 1520.43 4.35 17 20.61 4.31 14 21.23 4.19 21 22.06 4.03 10 23.19 3.84 1224.10 3.69 15 25.21 3.53 21 25.50 3.49 24 26.97 3.31 14 27.69 3.22 728.15 3.17 11 28.92 3.09 13 29.47 3.03 5 30.18 2.96 8 31.11 2.88 9 32.062.79 7

Another embodiment of the invention encompasses crystalline acetonitrilesolvate free base of the compound having the structure

FIG. 12 shows the X-ray powder diffraction pattern of crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamideacetronitrile solvate. The acetonitrile solvate form is characterized bydiffraction peaks corresponding to d-spacings as detailed in Table 8.

TABLE 8 Pos. [° Two Theta.] d-spacing [Å] Rel. Int. [%] 4.42 19.99 945.87 15.05 62 6.67 13.25 67 8.05 10.98 75 8.94 9.89 42 10.26 8.62 4411.32 7.82 35 11.89 7.45 43 13.50 6.56 94 13.68 6.47 73 14.03 6.31 2614.77 6.00 56 15.79 5.61 50 16.26 5.45 100 17.04 5.20 44 17.94 4.95 4618.50 4.80 53 18.83 4.71 50 19.33 4.59 40 20.15 4.41 48 21.17 4.20 4522.37 3.97 34 22.67 3.92 34 23.70 3.75 33 24.33 3.66 25 24.59 3.62 2225.29 3.52 22 26.27 3.39 17 26.81 3.33 18 27.62 3.23 21

Another embodiment of the invention encompasses X-ray amorphous freebase of the compound having the structure

FIG. 13 shows the X-ray powder diffraction pattern of X-ray amorphous(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidewhich is generated via desolvation of an acetonitrile solvate. The X-rayamorphous pattern displays a broad diffuse halo with only a single lowangle peak at approximately 5° two-theta.

Another embodiment of the invention encompasses crystalline acetonitrilesolvate free base of the compound having the structure

and having the following chemical name:(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamideacetonitrile solvate.

FIG. 14 shows the X-ray powder diffraction pattern for crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamideacetonitrile solvate. The acetonitrile solvate form is characterized bydiffraction peaks corresponding to d-spacings as detailed in Table 9.

TABLE 9 Pos. [° Two Theta.] d-spacing [Å] Rel. Int. [%] 4.22 20.92 1006.01 14.71 49 7.07 12.50 44 7.82 11.31 41 8.35 10.58 45 12.15 7.29 6012.83 6.90 66 13.92 6.36 59 15.20 5.83 48 17.21 5.15 61 19.23 4.62 5920.38 4.36 72

Another embodiment of the invention encompasses crystalline L-tartaricAcid cocrystal of the compound having the structure

FIG. 15 shows the X-ray powder diffraction pattern of crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamideL-tartaric acid cocrystal. The L-tartaric acid cocrystal form ischaracterized by diffraction peaks corresponding to d-spacings asdetailed in Table 10.

TABLE 10 Pos. [° Two Theta.] d-spacing [Å] Rel. Int. [%] 6.19 14.27 226.81 12.98 21 7.45 11.87 19 8.59 10.30 5 10.74 8.24 4 11.41 7.76 2612.18 7.26 8 12.45 7.11 8 12.95 6.84 12 13.75 6.44 5 14.43 6.14 15 15.295.79 100 15.74 5.63 10 16.22 5.46 81 16.99 5.22 51 17.78 4.99 26 18.164.89 5 18.75 4.73 68 19.56 4.54 22 20.08 4.42 13 20.54 4.32 10 21.074.22 10 21.69 4.10 17 22.20 4.00 11 22.86 3.89 44 23.27 3.82 11 23.743.75 34 24.21 3.68 26 25.33 3.52 10 26.17 3.41 10 27.02 3.30 27 27.473.25 7 27.96 3.19 9 28.37 3.15 7 29.17 3.06 11 29.57 3.02 13 30.02 2.9811 31.18 2.87 10 31.86 2.81 14 32.61 2.75 7 32.96 2.72 6 33.86 2.65 435.61 2.52 6 36.54 2.46 5 36.92 2.43 4 39.32 2.29 2

Another embodiment of the invention encompasses crystalline L-tartaricacid cocrystal of the compound having the structure

and having the following chemical name:(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamideL-tartaric acid cocrystal.

FIG. 16 shows the X-ray powder diffraction pattern for crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamideL-tartaric acid cocrystal. The L-tartaric cocrystal form ischaracterized by diffraction peaks corresponding to d-spacings asdetailed in Table 11.

TABLE 11 Pos. [° Two Theta.] d-spacing [Å] Rel. Int. [%] 7.35 12.02 511.32 7.82 20 12.27 7.21 12 12.89 6.87 6 14.31 6.19 11 15.20 5.83 5216.04 5.52 100 16.84 5.27 58 17.64 5.03 16 18.56 4.78 55 19.40 4.58 1819.94 4.45 9 20.57 4.32 14 20.92 4.25 12 21.49 4.13 14 21.94 4.05 1322.70 3.92 29 23.20 3.83 12 23.52 3.78 24 24.00 3.71 14 24.38 3.65 724.85 3.58 9 25.19 3.53 9 25.69 3.47 5 25.99 3.43 8 26.74 3.33 31 28.083.18 10 28.98 3.08 8 29.33 3.04 7 29.68 3.01 7 30.93 2.89 6 31.62 2.83 832.40 2.76 6 32.72 2.74 6 33.96 2.64 9

Another embodiment of the invention encompasses a crystalline free baseof the compound having the structure

and having the following chemical name:(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,5-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamide.

FIG. 17 shows the X-ray powder diffraction pattern for crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,5-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamide.The form is characterized by diffraction peaks corresponding tod-spacings as detailed in Table 12.

TABLE 12 Pos. [° Two Theta.] d-spacing [Å] Rel. Int. [%] 5.85 15.10 407.64 11.58 73 9.62 9.20 22 10.37 8.53 100 11.50 7.70 38 11.81 7.50 3712.87 6.88 19 13.92 6.36 26 14.49 6.11 41 15.52 5.71 67 16.86 5.26 6217.89 4.96 69 18.33 4.84 30 19.07 4.65 42 19.64 4.52 40 20.98 4.23 2222.60 3.93 41 23.68 3.76 35 24.36 3.65 37 25.47 3.50 24

ABBREVIATIONS

The following abbreviations are used throughout the specification.

-   Bs=benzenesulfonyl-   Boc=tert-butoxycarbonyl-   BOM=benzyloxymethyl-   BOP=(benzotriazole-1-yloxy)-tris(dimethylamino)phosphonium    hexafluorophosphate-   Cbz=benzyloxycarbonyl-   CDI=1,1′-carbonyldiimidazole-   CPME=cyclopentyl methyl ether-   DBU=1,8-diazabicyclo[5.4.0]undec-7-ene-   DCC=N,N-dicyclohexylcarbodiimide-   DCM=dichloromethane-   DCPE=1,3-bis(dicyclohexylphosphino)ethane-   DCPP=1,3-bis(dicyclohexylphosphino)propane-   DHP=3,4-dihydro-2H-pyran-   DMAc=N,N-dimethylacetamide-   DMF=N,N-dimethylformamide-   DMPU=1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone-   DMSO=dimethyl sulfoxide-   DPPA=diphenylphosphoryl azide-   EDC=N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride-   HATU=O-(7-azabenzotriazol-1-yl)-N,N,N′N′-tetramethyluronium HCl-   HCl=hydrochloric acid-   HOAt=1-hydroxy-7-azabenzotriazole-   HOPO=2-hydroxypyridine-N-oxide-   HOBT=1-hydroxybenzotriazole-   HOSu=N-hydroxysuccinimide-   IPA or iPA=isopropyl alcohol-   IPAc=isopropyl acetate-   LCAP=liquid chromatography area percent-   LiHMDS=lithium bis(trimethylsilyl)amide-   Ms=methanesulfonyl-   MOM=methoxymethyl-   MTBE=methyl tert-butyl ether-   NMP=N-methyl-2-pyrrolidone-   Ph=phenyl-   PTC=phase transfer catalyst-   RBF=round bottom flask-   RT=room temperature-   SEM=2-(trimethylsilyl)ethoxymethyl-   SFC=supercritical fluid chromatography-   TBDMS=tert-butyldimethylsilyl-   TEA=triethylamine-   TES=triethylsilyl-   THF=tetrahydrofuran-   THP=tetrahydropyranyl-   TIPS=triisopropylsilyl-   TMS=trimethylsilyl-   Ts=toluenesulfonyl

Previous methods for synthesizing compounds of Formula I are shown inSchemes 1 to 15 described below.

Scheme 1 illustrates a route to 3-aminopiperidinone intermediates oftype 1.5 which may be used to prepare compounds of the presentinvention. Aryl acetone 1.1 can be alkylated using the iodoalaninederivative 1.2 under basic conditions to provide keto ester 1.3.

Reductive amination followed by cyclization and epimerization providesprimarily cis-substituted lactam 1.4 as a racemic mixture. Chiralresolution using normal-phase liquid chromatography, for example, andremoval of the Boc protecting group with HCl in EtOAc furnishes3-aminopiperidinone 1.5 as a hydrochloride salt.

An alternative sequence to 3-aminopiperidinone intermediates of type 1.5is shown in Scheme 2. Reductive amination of keto ester 1.3 with ammoniafollowed by epimerization provides 2.1 as a mostly cis-substitutedracemic mixture. Chiral resolution of the enantiomers provides 2.2.N-Alkylation with LiHMDS as base, for example, and an alkyl halide orepoxide affords 1.4. Removal of the Boc protecting group with HCl thenaffords 1.5 as a hydrochloride salt.

A third method to 3-aminopiperidinone intermediates of type 1.5 is shownin Scheme 3. N-Alkylation of 5-bromo-6-methylpyridin-2(1H)-one (3.1)using cesium carbonate as base and an alkyl halide followed by nitrationprovides 3.2. Palladium-catalyzed cross-coupling with an aryl boronicacid then affords 3.3. Hydrogenation using platinum oxide under acidicconditions and chiral resolution of the mostly cis-substituted racemicproduct mixture provides 1.5 as a single enantiomer.

A synthetic route to 3-aminopiperidinone intermediates of type 4.4 isshown in Scheme 4. Aryl acetonitrile 4.1 can be alkylated using theiodoalanine derivative 1.2 under basic conditions to provide cyano ester4.2. Reductive cyclization using hydrogen and palladium hydroxide oncarbon or Raney nickel, epimerization, and chiral resolution affords cislactam 4.3 as a single enantiomer. N-Alkylation and removal of the Bocprotecting group then provides 4.4 as a hydrochloride salt.

Scheme 5 illustrates an alternative route to 3-aminopiperidinoneintermediates of type 4.4. The arylacetonitrile 5.1 may be condensedwith acrylate 5.2 at elevated temperature to give the 4-cyanobutanoateester 5.3. Hydrogenation of nitrile 5.3 using Raney nickel catalyst andan ethanolic solution of ammonia affords the corresponding amineproduct, which typically cyclizes in situ to provide piperidinone 5.4.N-Alkylation of lactam 5.4 may be accomplished by a variety of methodsknown to those skilled in the art of organic synthesis, the exact choiceof conditions being influenced by the nature of the alkylating agent,R¹X. Electrophilic azidation of the resulting substituted lactam 5.5 canbe accomplished using similar methodology to that described by Evans andcoworkers (Evans et al. (1990) J. Am. Chem. Soc. 112, 4011-4030) toprovide the azide 5.6 as a mixture of diastereoisomers, which can beseparated by chromatography. The desired cis diastereomer of azide 5.6may be reduced by catalytic hydrogenation in the presence ofdi-tert-butyl dicarbonate to give the corresponding Boc-protected amine5.7, and separation of the enantiomers using chiral HPLC or SFC leads tothe (3S,5S)-isomer 5.8. Finally, standard deprotection affords thedesired 3-aminopiperidinone intermediate 4.4 as a hydrochloride salt.

Another approach to 3-aminopiperidinone intermediates of interest, whichis particularly useful for preparing3-amino-6-methyl-5-arylpiperidin-2-ones such as 1.5, is outlined inScheme 6. The pyridin-2(1H)-one 3.1 may be converted to theN-substituted pyridinone 6.1 by treatment with a suitable electrophile(R¹X) under basic conditions. Pyridinone 6.1 can then be subjected toSuzuki-Miyaura coupling with the boronic acid 6.2, and the resulting5-arylpyridinone 6.3 may be hydrogenated using, for example,platinum(IV) oxide catalyst to afford the corresponding5-arylpiperidinone 6.4, which is usually obtained as predominantly thecis isomer. Further elaboration of piperidinone 6.4 may be achievedusing analogous methodology to that described in Scheme 5. Specifically,electrophilic azidation followed by one-pot reduction and Boc protectionleads to carbamate 6.6, and the desired enantiomer may be obtained usingchiral chromatography. In some cases, the desired diastereomer of azide6.5 may be isolated as a racemic mixture of the (3S,5S,6R)- and(3R,5R,6S)-isomers following silica gel chromatography of the crudeproduct, and this mixture may be elaborated as outlined in Scheme 6. Inother cases, it may be advantageous to take a mixture of diastereomersof azide 6.5 forward to the corresponding carbamate 6.6. The mixture ofcarbamate 6.6 diastereomers may be epimerized under basic conditions,such as potassium carbonate in EtOH, to afford a mixture that issignificantly enriched in the desired (3S,5S,6R)- and(3R,5R,6S)-isomers, further purification may be employed to obtain theenantiomer of interest as outlined herein.

A synthetic route to the azaoxindole pyridine acid intermediate 7.4 isshown in Scheme 7. Diazotization of aminopyridine 7.1, whose preparationis described in WO 2008/020902, followed by treatment with potassiumiodide in the presence of NaNO₂ provides iodide 7.2. Palladium-catalyzedcarbonylation in methanol then affords ester 7.3, which may besaponified with sodium hydroxide to furnish 7.4.

An alternative synthesis of the azaoxindole pyridine acid intermediate7.4 is shown in Scheme 8. Esterification of diacid 8.1 followed bybromination provides 8.2. Reduction with sodium borohydride thenfurnishes diol 8.3. Alkylation of the protected azaoxindole 8.4 with thebis-mesylate produced from 8.3 affords the spirocycle 8.5.Palladium-catalyzed carbonylation in methanol followed by chiralresolution gives ester 8.6 as a single enantiomer. Removal of the SEMprotecting group under acidic conditions and hydrolysis of the esterusing sodium hydroxide then provides 7.4.

A synthetic route to diazaoxindole carboxylic acid intermediate 9.7 isshown in Scheme 9. Esterification of acid 9.1 is followed by vinylationunder palladium catalysis to afford divinyl pyridine 9.2. Ozonolysiswith a borohydride reductive workup then yields diol 9.3. Aftermesylation and treatment with sodium choride, the resulting dichlorointermediate 9.4 can be alkylated with oxindole 9.5 under basicconditions to give spirocycle 9.6, following chiral resolution of theenantiomers. Dechlorination under buffered hydrogenation conditions andacidic deprotection affords acid 9.7.

Useful derivatives of the intermediates described herein may be preparedusing well-precedented methodology. One such example is illustrated inScheme 10, in which the azaoxindole intermediate 7.4 is converted to thecorresponding nitrile derivative 10.2, which may be used to preparecompounds of the present invention. Bromination of 7.4 withN-bromosuccinimide in boron trifluoride dihydrate provides the bromoderivative 10.1, which may be converted to the desired nitrile 10.2using zinc cyanide and a palladium catalyst as shown.

A synthetic route to the azaoxindole indane acid intermediate 11.17 isshown in Scheme 11. Esterification of diacid 11.1 followed byhydrogenation using palladium on carbon as a catalyst provides aniline11.2. Dibenzylation under basic conditions with heat affords 11.3, andreduction of the diester with LiAlH₄ furnishes diol 11.4. Chlorinationwith thionyl chloride provides benzyl chloride 11.5. Palladium-catalyzedamination of bromide 11.6 with tert-butylamine gives 11.7. Sequentialtreatment with n-hexyllithium and methyl chloroformate (2×) affordsazaoxindole ester 11.8. Alkylation with the benzylchloride 11.5 underbasic conditions in the presence of the cinchonidine-derived catalyst11.12 (prepared via the alkylation of cinchonidine 11.10 with benzylbromide 11.11) affords spirocycle 11.13. Deprotection of the azaoxindoleusing methanesulfonic acid with heat and debenzylation under standardhydrogenation conditions provides aniline 11.14. Diazotization followedby treatment with potassium iodide provides iodide 11.15.Palladium-catalyzed carbonylation in methanol then affords ester 11.16,which may be saponified with sodium hydroxide to furnish 11.17.

An alternative synthesis of the azaoxindole pyridine acid intermediate11.17 is shown in Scheme 12. Alkylation of the azaoxindole ester 11.8with dibenzyl bromide 12.1 followed by chiral resolution of theenantiomers provides ester 12.2. Sequential deprotection of theazaoxindole using methanesulfonic acid with heat and hydrolysis of theester provides 11.17.

A synthetic route to the diazaoxindole carboxylic acid intermediate 13.4is shown in Scheme 13. Alkylation of dibromide 12.1 with oxindole 9.5under basic conditions and subsequent chiral resolution affordsspirocycle 13.2. Dechlorination under buffered hydrogenation conditionsand ester hydrolysis then affords acid 13.4.

Useful derivatives of the intermediates described herein may be preparedusing well-precedented methodology. One such example is illustrated inScheme 14, in which the azaoxindole intermediate 11.17 is converted tothe corresponding nitrile derivative 14.2, which may be used to preparecompounds of the present invention. Treatment of 11.17 with bromine inacetic acid provides the bromo derivative 14.1, which may be convertedto the desired nitrile 14.2 using zinc cyanide and a palladium catalystas shown.

Scheme 15 illustrates conditions that can be used for the coupling of3-aminopiperidinone intermediates, such as 15.1, and carboxylic acidintermediate 15.2, to produce, in this instance, amides 15.3. Thesestandard coupling conditions are representative of the methods used toprepare the compounds of the present invention.

The previous methods for synthesizing the lactam intermediate sufferedfrom one or more drawbacks: racemic mixture was separated bychiral-HPLC, separation of diasteromixture by crystallization and/or useof costly PtO₂. The process of the instant invention utilizes atransaminase induced dynamic kinetic resolution providing highdiastereoselectivity at positions C5 and C6. N-mono-trifluoroethylationwas discovered and developed. Cis and trans isomer at the alpha positionof the amine was successfully controlled by crystallization in thepresence of arylaldehyde derivatives. Overall, synthetic steps areshorter, practical and efficient and yield is dramatically improved.

Example 1 Isopropyl2-(tert-butoxycarbonylamino)-3-(methylsulfonyloxy)propanoate (2)

To a solution of N-tert-butyl-L-serine isopropyl ester 1 (12 g, 48.5mmol)* and methanesulfonyl chloride (4.0 ml) in dichloromethane (100mL), triethylamine (7.2 ml) was added slowly under an ice bath. Thereaction mixture was stirred at room temperature for 1 h, then 1 N HCl(40 mL) was added with stirring. The organic layer was separated, washedwith 1 N HCl (40 ml) and brine (40 ml), dried over MgSO₄, andconcentrated in vacuo to give 2 (14.5 g, 91.9%) as a solid. ¹H NMR(CDCl₃, 500 MHz): δ 5.45 (s, broad, 1H), 5.13 (m, 1H), 4.62-4.47 (m,3H), 3.04 (s, 3H), 1.48 (s, 9H), 1.31 (d, J=6.4 Hz, 6H); ¹³C NMR (CDCl₃,100 MHz): δ 168.0, 135.1, 80.6, 70.5, 69.1, 53.3, 37.4, 28.3, 21.7,21.6; HRMS m/z calcd. for C₁₂H₂₃NO₇S 348.1087 (M+Na). found 348.1097

* preparation of 1 was reported in J. Med. Chem., 2010, 53, 6825-68376825

Isopropyl 2-(tert-butoxycarbonylamino)-3-iodopropanoate (3)

To a solution of 2 (392 g) in acetone (3.14 L), sodium iodide (542 g)was added. The reaction temperature went up to 29° C. from 17° C. Thereaction mixture was maintained at room temperature over weekend. Themixture was filtrated and washed with MTBE. The filtrate and washingswere combined and concentrated. The residue was treated with MTBE andwater with a small amount of sodium thiosulfate. The organic layer waswashed with water and concentrated to an oil. The oil was charged slowlyinto a mixture of water (2 L) and DMF (300 ml) with a small amount ofseed at 5° C. The crystals were filtered and dried to give 3 (400 g, 93%yield).

Isopropyl 4-(4-bromophenyl)-2-(tert-butoxycarbonylamino)-5-oxohexanoate(5) and isopropyl 4-phenyl-2-(tert-butoxycarbonylamino)-5-oxohexanoate(6)

To a solution of 4 (51.7 g, 243 mmol) in DMF (850 ml) was added 3 (88 g,246 mmol). The resulting solution was cooled to 5° C. and Cs₂CO₃ (240 g)was added in one portion. The suspension was warmed to 15° C. andstirred at this temperature for 2.5 h. Additional Cs₂CO₃ (25 g) wascharged and the mixture was stirred for additional 8 h or until HPLCanalysis indicated the conversion was greater than 95%. The batch wasthen slowly quenched into a mixture of 2N HCl (850 mL) and MTBE (900 mL)at 5-20° C. Organic layer was separated and aqueous layer extracted withMTBE (400 mL). Combined organic layers were washed with 5% NaHCO₃solution (400 mL) twice. The resulting solution containing desiredproduct 5 (90% LC purity) was concentrated under vacuum. The residue wasdissolved in isopropanol (1 L). To the solution was added K₂CO₃ (25 g),potassium formate (34 g) and 10% Pd/C (20 g). The mixture was warmed upto 60° C. and stirred for 2 h. The mixture was filtered after cooling toroom temperature. The HPLC analysis of the filtrate indicated that thesolution contained 6 (54.7 g, 95 wt %, 62% yield). The crude product wasused directly in the next step without further purification. Thecompound 6 is a mixture of two pair of diastereomers 6-1 and 6-2,partially separable by flash chromatography on silica gel with ethylacetate and heptane as a eluant (1:10). 6-1: ¹H NMR (CDCl₃, 500 MHz): δ7.35 (m, 2H), 7.30 (m, 1H), 7.20 (m, 2H), 5.17 (br, 1H), 4.95 (m, 1H),4.76 (br, 1H), 3.73 (m, 1H), 2.70 (br, 1H), 2.07 (s, 1H), 1.45 (s, 9H),1.29 (d, J=6.6 Hz, 3H), 1.28 (d, J=6.6 Hz, 3H); 6-2: ¹H NMR (CDCl₃, 500MHz): δ 5.12 (m, 1H), 4.70 (m, 1H), 3.27 (m, 1H), 2.80 (m 1H), 2.34 (s,3H), 1.50 (s, 9H), 1.26 (d, J=6.6 Hz, 3H), 1.25 (d, J=6.6 Hz, 3H); HRMSm/z: cacld. for 6-1: C₂₀H₂₉NO₅ 386.1938 (M+Na). found 386.1947.

Isopropyl 2-((tert-butoxycarbonyl)amino)acrylate (7)

To a solution of 1 (10.05 g, 40.6 mmol) in DMF (100 mL) was added MsCl(4.12 mL, 52.8 mmol) under ice-cooling. Triethylamine (14.16 mL, 102.0mmol) was then added dropwise via an addition funnel over 30 min, whilemaintaining the reaction temperature between 0-5° C. When the additionwas complete, the cooling bath was removed and the yellow heterogeneousreaction mixture was aged at room temperature under N₂ for overnight.The reaction mixture was diluted with ice cold water (1 L) and MTBE (1L). The layers were separated and the aqueous layer was back-extractedwith MTBE (500 mL). The organic layers were combined and washed with 1Mcitric acid (750 mL), water (1 L) and then 10% aqueous NaCl (1 L). Theorganic solution contained 7 (8.652 g, 93% yield). Solvent was switchedto DMSO at <40° C. and use solution directly in next step.

Isopropyl 4-phenyl-2-(tert-butoxycarbonylamino)-5-oxohexanoate (6)

Compound 6 was prepared from 7 in DMSO in the presence of 0.5 equiv.Cs₂CO₃ with 1.05 equiv. of phenylacetone at room temperature in 79%yield.

tert-Butyl(5S,6R)-6-methyl-2-oxo-5-phenylpiperidin-3-ylcarbamate (8)

To a 5 L RBF with overhead stirring, a temperature control, a pH probeand a base addition line, was added sodiumtetraborate decahydrate (26.7g) and DI water (1.4 L). After all solids were dissolved, isopropylamine(82.8 g) was added. The pH of the buffer was adjusted to pH 10.5 using 6N HCl. The buffer was cooled to room temperature. Then,pyridoxal-5-phosphate (2.8 g) and SEQ ID NO: 1 (70 g) were added andslowly dissolved at room temperature.

An oil (197.9 g, containing 70.7 wt % keto ester 6 (140 g, 0.385 mol)were dissolved in DMSO (1.4 L). The solution was added to the flask over5-10 min and the reaction was heated to 55° C. The pH was adjusted to10.5 according to a handheld pH meter and controlled overnight with anautomated pH controller using 8 M aqueous isopropylamine. The reactionwas aged for 24 h.

After confirmation of >95A % conversion by HPLC, the reaction wasextracted by first adding a mixture of iPA:IPAc (3:4, 2.8 L) andstirring for 20 min. The phases were separated and the aqueous layer wasback extracted with a mixture of iPA:IPAc (2:8, 2.8 L). The phases wereseparated, the organic layers were combined and washed with DI water(0.5 L). The HPLC based assay yield in the organic layer was 8 (114.6 g)with >60:1 dr at the positions C5 and C6. The ratio of stereoisomers atposition C2 was ˜1:1. The extract was concentrated and dissolved inCH₂Cl₂. The organic solution was washed with water then saturatedaqueous NaCl, concentrated and crystallized from MTBE/n-hexane (2:3).The crystal was filtered at room temperature and washed withMTBE/n-hexane (2:3) and dried to afford a cis and trans mixture (˜1:1.2)of the lactam 8 (99.6 g, 80.0%) as crystals.

cis: trans (˜1:1.2) mixture but NMR integration was reported as 1:1 (forproton number counts) Mp 87-90.9° C.; ¹H NMR (CDCl₃, 400 MHz): δ7.40-7.20 (m, 8H, cis and trans), 7.16-7.12 (m, 2H, cis and trans); 6.56(broad s, 1H, trans), 6.35 (broad s, 1H, cis), 5.57 (broad d, J=4.6 Hz,1H, cis), 5.34 (broad d, J=5.7 Hz, 1H, trans), 4.33-4.15 (m, 2H, cis andtrans), 3.93 (m, 1H, trans), 3.81 (m, 1H, cis), 3.41 (dt, J=11.8, 5.0Hz, 1H, cis), 3.29 (dt, J=8.0, 4.4 Hz, 1H, trans), 2.74 (m, 1H, cis),2.57 (m, 1H, trans), 2.23 (ddd, J=13.5, 8.0, 4.4 Hz, trans), 2.07 (q,J=11.8 Hz, 1H, cis), 1.46 (s, 9H, cis), 1.42 (s, 9H, trans), 1.05 (d,J=6.9 Hz, 3H, trans), 0.89 (d, J=6.9 Hz, 3H, cis); ¹³C NMR (CDCl₃, 100MHz): δ 171.5₂ (cis), 171.4₆ (trans), 156.0₄ (cis or trans), 155.93 (cisor trans), 140.8 (cis), 139.9 (trans), 128.8 (trans), 128.7 (cis), 128.6(trans), 128.1 (cis), 127.2₅ (trans), 127.1₈ (cis), 79.9₈ (trans), 79.9₁(cis), 52.4 (trans), 51.8 (broad, cis), 51.7 (cis), 49.0 (broad, trans),42.1 (cis), 41.9 (trans), 32.4 (broad, trans), 30.1 (cis), 28.5₇ (cis ortrans), 28.5₃ (cis or trans), 18.3 (cis), 18.1 (broad, trans); HRMS m/zcacld. for C₁₇H₂₄N₂O₃327.1679 (M+Na). found 327.1696

tert-Butyl(5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-ylcarbamate(9) andtert-butyl(5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl(2,2,2-trifluoroethyl)carbamate(10)

To the solution of 8 (480 g, 1.58 mol) in anhydrous THF (3.8 L) wasadded lithium tert-amoxide solution in heptane (512 mL, 3.1 M, 1.58 mol)over about 15 min while maintaining the reaction temperature between 15and 20° C. The resulting solution was then cooled to a temperaturebetween 0 and 2° C. 2,2,2-Trifluoroethyl trifluoromethanesulfonate (368g, 1.58 mol) was added over 15 min while maintaining the reactiontemperature between 0 and 3° C. The solution was agitated at 0° C. for15 min. DMPU (300 ml) was charged to the mixture through an additionalfunnel over 30 min while maintaining the reaction temperature between 0and 3° C. The resulting solution was agitated at 0° C. for 2.5 h.Another 2,2,2-trifluoroethyl trifluoromethanesulfonate (182 g, 0.79 mol)was added to the mixture over 10 min followed by another 3.1 M lithiumtert-amoxide solution (104 mL) while maintaining the reactiontemperature between 0 and 3° C. The batch was agitated for another 2.5 hat 0° C. The mixture was quenched into a mixture of heptane (4.8 L),water (3.4 L) and 2N HCl solution (280 mL) below 15° C. The phases wereseparated. The aqueous phase was extracted with heptane (4 L). Thecombined organic phase was washed with water (2 L). The solution wasconcentrated to a volume of about 1 L under vacuum between 25 and 50° C.The crude material was passed through a short silica gel plug withheptane/ethyl acetate. The resulting solution was concentrated undervacuum until distillation stopped at a temperature below 50° C.,dissolved in IPAc (2 L) and used for the next processing step. The assayyield of 9 for both cis and trans isomers was 85% in the ratio of ˜8 to1.

Analytically pure cis and trans isomers of 9 were isolated bychromatography on silica gel with ethyl acetate and heptane as eluant. 9(cis): ¹H NMR (CDCl₃, 500 MHz): δ 7.30 (m, 5H), 5.75 (s, broad, 1H),4.35 (m, 1H), 4.15 (m, 1H), 3.80 (m, 1H), 3.50 (m, 1H), 3.17 (m, 1H),2.45 (m, 2H), 1.45 (s, 9H), 0.93 (d, J=6.7 Hz, 3H); ¹³C NMR (CDCl₃, 100MHz): δ 170.3, 155.9, 140.0, 128.6, 127.6, 127.1, 124.6 (q, J=279 Hz),79.7, 58.7, 52.2, 45.3 (q, J=33.7 Hz), 41.9, 28.3, 27.4, 13.4; HRMS: m/zcalcd for C₁₉H₂₅F₃N₂O₃ 387.1890 (M+H). found: 387.1899. 9 (trans): ¹HNMR (CDCl₃, 500 MHz): δ 7.40 (m, 2H), 7.30 (m, 3H), 5.55 (br, 1H), 4.53(br, 1H), 4.45 (m, 1H), 3.78 (m 2H), 3.45 (m, 1H), 3.0 (m, 1H), 2.12 (m,1H), 1.46 (s, 9H), 1.12 (d, J=7.0 Hz, 3H); ¹³C NMR (CDCl₃, 100 MHz): δ170.2, 155.9, 139.6, 128.7, 127.9, 127.4, 124.3 (q, J=279 Hz), 80.0,59.6, 49.1, 46.9 (q, J=34.0 Hz), 42.1, 28.3, 25.3, 13.4; HRMS: m/z calcdfor C₁₉H₂₅F₃N₂O₃ 387.1890 (M+H). found 387.1901.

(3S,5S,6R)-6-Methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-aminium4-nitrobenzoate (11)

To a solution of the crude 9 obtained from above experiment (10 g assay,25.9 mmol) in iPAC (8 ml) was added p-toluenesulfonic acid monohydrate(6.7 g, 35.2 mmol) and the mixture was stirred at 50-60° C. for 3 hruntil the reaction was completed (>99%). The solution was cooled to15-20° C., and washed with 10% aqueous K₂CO₃ followed by water. Theaqueous layers were re-extracted with iPAc (5 ml). The organic layerswere combined and heated to 55-60° C. 4-Nitrobenzoic acid (3.9 g, 23.2mmol) was slowly added in 20 min. The mixture was slowly cooled to roomtemperature. 5-Nitro-2-hydroxylbenzaldehyde (50 mg) was added and thebatch was agitated for at least 12 h. The mixture was filtrated andwashed with MeCN to give 11 as crystals. Optionally, a slurry in MeCNwas carried out for further purification of 11. The isolated yield was90%. Mp 205-208° C.; ¹H NMR (DMSO-d₆, 400 MHz): δ 8.21 (dd, J=9.0, 2.1Hz, 2H), 8.08 (dd, J=9.0, 2.1 Hz, 2H), 7.37 (t, J=7.4 Hz, 2H), 7.28 (t,J=7.4 Hz, 1H), 7.24 (d, J=7.4 Hz, 2H), 4.65 (ddd, J=15.1, 9.7, 7.7 Hz,1H), 3.72-3.98 (m, 3H), 3.57 (m, 1H), 2.46 (q, J=12.6 Hz, 1H), 2.25 (m,1H), 0.90 (d, J=6.4 Hz, 3H); ¹⁹F NMR (DMSO-d₆, 376 MHz): δ −69 (s); ¹³CNMR (DMSO-d₆, 100 MHz): δ 168.7, 167.3, 148.3, 143.8, 140.1, 130.1,128.6, 127.4, 127.0, 124.9 (q, J=280.9 Hz), 122.8, 58.7, 49.8, 44.5 (q,J=32.7 Hz), 40.6, 25.3, 13.2.

(5S,6R)-3-Amino-6-methyl-5-phenyl-1-(2,2,2-trifluoroethyl)piperidin-2-one(12)

To a mixture of 8 (20.0 g, 65.7 mmol) and Na₂S₂O₃ (0.52 g, 3.3 mmol) inTHF (200 mL) was added tert-BuOLi (6.8 g, 85 mmol) at 16° C. The mixturewas stirred at 16° C. for 15 min followed by addition of trifluoroethyltrifluoromethansulfonate (20.6 g, 89 mmol) in one portion. The resultingmixture was stirred for 18 h at 16° C. The reaction mixture was thenquenched by addition of toluene (70 mL) followed by 0.5N HCl solution(50 mL). The aqueous layer was separated and extracted with toluene (20mL). The combined organic layer contained 87% of 9, 6% of 10 and 6% of 8by HPLC and yield for the desired product 9 was 87%. The organic layerwas then stirred with 3N HCl solution (80 ml) and tetrabutylammoniiumbromide (0.8 g) for about 3 h until HPLC analysis indicated selectiveremoval of the Boc group in the unreacted 8 was completed. The aqueouslayer was removed. The organic layer containing 9 and 10 was thenconcentrated under vacuum at 60° C. to remove most of solvent. Theresidue was dissolved in MTBE (60 mL), and 5N HCl solution (65 mL) wasadded. The diphasic solution was agitated vigorously at 50° C. for about5 h until the deprotection of 9 was completed while 10 was mainlyintact. After addition of heptane (30 mL) to the mixture, the organiclayer was separated at 45° C. The aqueous layer was diluted with water(60 mL) and resulting aqueous and washed with heptane (30 mL) at 45° C.The aqueous solution was then mixed with MTBE (100 mL) and basified with10 N NaOH solution until the pH of the mixture was about 10. The organiclayer was separated and the aqueous layer was back-extracted with MTBE(60 mL). The combined organic layers were washed with brine (60 mL). Theresulting organic solution was suitable for next reaction. The solutionwas contained 12 (15.6 g, 83% from 8) with 97% LC purity as a mixture oftwo diastereomers (cis and trans) in 4 to 1 ratio.

(3S,5S,6R)-6-Methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidin-3-aminium4-methylbenzoate (13)

To a suspension of 4-methylbenzoic acid (6.8 g, 49.9 mmol) and3,5-dichlorosalicylaldehyde (93 mg, 0.49 mmol) in MTBE (40 mL) was addeda solution of 12 (13.9 g, 48.5 mmol) in MTBE (about 150 mL) over 1 h at50° C. The resulting suspension was agitated for about 3 h at 50° C. Thesolids were collected by filtration after cooling to −5° C. over 1 h.The cake was washed with MTBE (50 mL). The solids were dried in a vacuumoven to give 13 (17.6 g, 86%) as crystals with 99.5% LC purity and 99.6%de. ¹H NMR (DMSO-d₆, 400 MHz): δ 7.85 (d, J=8.1 Hz, 2H), 7.40 (m, 2H),7.25 (m, 5H), 6.0 (br, 3H), 4.65 (m, 1H), 3.65-3.80 (m, 2H), 3.45-3.65(m, 2H), 2.35 (s, 3H), 2.30 (m, 1H), 2.15 (m, 1H), 0.88 (d, J=6.5 Hz,3H); ¹³C NMR (DMSO-d₆, 100 MHz): δ 172.4, 168.5, 142.1, 141.1, 130.9,129.7, 129.2, 129.0, 128.0, 125.5 (q, J=279 Hz), 59.1, 51.6, 45.1 (q,J=32 Hz), 41.6, 28.0, 21.5, 13.9.

(S)—N-((3S,5S,6R)-6-Methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidetrihydrate (15)

To a suspension of 11 (465 g, 96% wt, 0.99 mol) in iPAc (4.6 L) wasadded 5% aqueous K₃PO₄ (4.6 L). The mixture was stirred for 5 min. Theorganic layer was separated and washed with 5% aqueous K₃PO₄ (4.6 L)twice and concentrated in vacuo and dissolved in acetonitrile (1.8 L).

To another flask was added 14 (303 g, 91.4 wt %), acetonitrile (1.8 L)and water (1.8 L) followed by 10 N NaOH (99 mL). The resulting solutionwas stirred for 5 min at room temperature and the chiral amine solutionmade above was charged to the mixture and the container was rinsed withacetonitrile (900 mL). HOBT hydrate (164 g) was charged followed by EDChydrochloride (283 g). The mixture was agitated at room temperature for2.5 h. To the mixture was added iPAc (4.6 L) and organic layer wasseparated, washed with 5% aqueous NaHCO₃ (2.3 L) followed by a mixtureof 15% aqueous citric acid (3.2 L) and saturated aqueous NaCl (1.2 L).The resulting organic layer was finally washed with 5% aqueous NaHCO₃(2.3 L). The organic solution was concentrated below 50° C. anddissolved in methanol (2.3 L). The solution was slowly added to amixture of water (6 L) and methanol (600 mL) with ˜2 g of seed crystal.And the resulting suspension was stirred overnight at room temperature.Crystals were filtered, rinsed with water/methanol (4 L, 10:1), anddried under nitrogen flow at room temperature to provide 15 (576 g, 97%yield) as trihydrate.

¹H NMR (500 MHz, CDCl₃): δ 10.15 (br s, 1H), 8.91 (br s, 1H), 8.21 (d,J=6.0 Hz, 1H), 8.16 (dd, J=5.3, 1.5 Hz, 1H), 8.01 (br s, 1H), 7.39-7.33(m, 2H), 7.31-7.25 (m, 1H), 7.22-7.20 (m, 2H), 7.17 (dd, J=7.4, 1.6 Hz,1H), 6.88 (dd, J=7.4, 5.3 Hz, 1H), 4.94 (dq, J=9.3, 7.6 Hz, 1H),4.45-4.37 (m, 1H), 3.94-3.87 (m, 1H), 3.72 (d, J=17.2 Hz, 1H), 3.63-3.56(m, 2H), 3.38-3.26 (m, 1H), 3.24 (d, J=17.3 Hz, 1H), 3.13 (d, J=16.5 Hz,1H), 2.78 (q, J=12.5 Hz, 1H), 2.62-2.56 (m, 1H), 1.11 (d, J=6.5 Hz, 3H);¹³C NMR (126 MHz, CD₃CN): δ 181.42, 170.63, 166.73, 166.63, 156.90,148.55, 148.08, 141.74, 135.77, 132.08, 131.09, 130.08, 129.66, 129.56,128.78, 128.07, 126.25 (q, J=280.1 Hz), 119.41, 60.14, 53.07, 52.00,46.41 (q, J=33.3 Hz), 45.18, 42.80, 41.72, 27.79, 13.46; HRMS m/z: calcdfor C₂₉H₂₆F₃N₅O₃ 550.2061 (M+H). found 550.2059.

Alternative Procedure for 15

To a suspension of 13 (10 g, 98 wt %, 23.2 mmol) in MTBE (70 mL) wasadded 0.6 N HCl (42 mL). The organic layer was separated and extractedwith another 0.6 N HCl (8 mL). The combined aqueous solution was washedwith MTBE (10 mL×3). To the resulting aqueous solution was addedacetonitrile (35 mL) and 14 (6.66 g, 99 wt %). To the resultingsuspension was neutralized with 29% NaOH solution to pH 6. HOPO (0.26 g)was added followed by EDC hydrochloride (5.34 g). The mixture wasstirred at room temperature for 6-12 h until the conversion was complete(>99%). Ethanol (30 ml) was added and the mixture was heated to 35° C.The resulting solution was added over 2 h to another three neck flaskcontaining ethanol (10 mL), water (30 mL) and 15 seeds (0.4 g).Simultaneously, water (70 mL) was also added to the mixture. Thesuspension was then cooled to 5° C. over 30 min and filtered. The cakewas washed with a mixture of ethanol/water (1:3, 40 mL). The cake wasdried in a vacuum oven at 40° C. to give 15 trihydrate (13.7 g, 95%) ascrystals.

Example 2 N-Methoxy-N-methyl-2-(2,3,6-trifluorophenyl)acetamide (17)

To a solution of DMF (58.1 mL, 750 mmol) in iPAc (951 mL) was addedPOCl₃ (55.9 mL, 600 mmol) under ice-cooling. After aged for 1 h underice-bath, acid 16 (95 g, 500 mmol) was added under ice-cooling. Thesolution was stirred under ice-cooling for 30 min. The solution wasadded over 30 min into a solution of K₂CO₃ (254 g, 1.835 mol) andNHMe(OMe)HCl (73.2 g, 750 mmol) in water (951 mL) below 8° C. After agedfor 30 min below 8° C., the organic layer was separated, washed withwater (500 mL) twice and sat. NaCl aq (100 mL) once, and concentrated invacuo to afford 17 as an oil (117.9 g, 97.7 wt %, 99% yield). ¹H NMR(CDCl₃, 400 MHz); δ 7.05 (m, 1H), 6.82 (m, 1H), 3.86 (s, 2H), 3.76 (s,3H), 3.22 (s, 3H); ¹⁹F NMR (CDCl₃, 376.6 MHz); δ −120.4 (dd, J=15.1, 2.7Hz), −137.9 (dd, J=20.8, 2.7 Hz), −143.5 (dd, J=20.8, 15.1 Hz); ¹³C NMR(CDCl₃, 100 MHz); δ 169.4, 156.9 (ddd, J=244, 6.2, 2.7 Hz), 149.3 (ddd,J=249, 14.4, 8.4 Hz), 147.1 (ddd, J=244, 13.1, 3.5 Hz), 115.5 (ddd,J=19.4, 9.9, 1.5 Hz), 133.4 (dd, J=22.3, 16.4 Hz), 110.2 (ddd, J=24.8,6.7, 4.1 Hz), 32.4 (broad), 26.6 (m); HRMS m/z calcd for C₁₀H₁₀F₃NO₂234.0736 (M+H). found 234.0746.

1-(2,3,6-Trifluorophenyl)propan-2-one (18)

A mixture of CeCl₃ (438 g, 1779 mmol) and THF (12 L) was heated at 40°C. for about 2 h then cooled to 5° C. Methylmagensium chloride in THF (3M, 3.4 L) was charged at 5-9° C. and then it was warmed up to 16° C. andheld for 1 h. The suspension was re-cooled to −10 to −15° C. A solutionof 17 (1.19 kg) in THF (2.4 L) was charged into the suspension over 15min. After confirmation of completion of the reaction, the reactionmixture was transferred to a cold solution of hydrochloric acid (2 N,8.4 L) and MTBE (5 L) in 5-10° C. The aqueous phase was separated andthe organic layer was washed with aqueous 5% K₂CO₃ (6 L) and then 10%aqueous NaCl (5 L). The organic layer was dried over Na₂SO₄,concentrated to give crude 18 (917 g, >99 wt %) in 95% yield. The crude18 was used in the next step without further purification. Analyticallypure 18 was obtained by silica gel column.

¹H NMR (CDCl₃, 400 MHz); δ 7.07 (m, 1H), 6.84 (m, 1H), 3.82 (s, 2H),2.28 (s, 3H); ¹⁹F NMR (CDCl₃, 376.6 MHz); δ −120.3 (dd, J=15.3, 2.5 Hz),−137.8 (dd, J=21.2, 2.5 Hz), −143.0 (dd, J=20.2, 15.3 Hz); ¹³C NMR(CDCl₃, 100 MHz); δ 202.2, 156.5 (ddd, J=244, 6.3, 2.9 Hz), 148.9 (ddd,J=249, 14.4, 8.6 Hz), 147.0 (ddd, J=244, 13.1, 3.5 Hz), 115.7 (ddd,J=19.4, 10.5, 1.2 Hz), 112.8 (dd, J=22.7, 17.0 Hz), 110.3 (ddd, J=24.8,6.7, 4.1 Hz), 37.2 (d, J=1.2 Hz), 29.3.

Isopropyl2-((tert-butoxycarbonyl)amino)-5-oxo-4-(2,3,6-trifluorophenyl)hexanoate(19)

To a solution of 18 (195 g, 1.03 mol) in MTBE (1.8 L) was added zincbromide (67 g, 0.30 mol) followed by 2 (390 g, 1.2 mol). tert-BuOLi (290g, 3.6 mol) was then added in several portions while maintaining thereaction temperature below 40° C. The resulting mixture was stirred at35° C. for 24 h and quenched into a mixture of 2 N HCl (5.6 L) andheptane (5 L) at 0° C. The organic layer was separated and washed with5% aqueous NaHCO₃ (5 L) twice. The resulting organic solution wasconcentrated under vacuum. The residue was dissolved in heptane (2 L)and the solution was concentrated again under vacuum. The resulting oilwas dissolved in DMSO (2.5 L) and the solution was used in the next stepwithout further purification. HPLC analysis indicated that the solutioncontained the desired product 19 (290 g, 67% yield) as the majorcomponent along with 5% of starting material 18. The analytically pureproduct 19 as one pair of diastereomers was isolated by chromatographyon silica gel with ethyl acetate and heptane mixture as an eluant. HRMS:m/z calcd for C₂₀H₂₆F₃NO₅ 418.1836 (M+H). found 418.1849.

tert-Butyl((5S,6R)-6-methyl-2-oxo-5-(2,3,6-trifluorophenyl)piperidin-3-yl)carbamate(20)

To a 0.5 L cylindrical Sixfors reactor with an overhead stirring, atemperature control, a pH probe and a base addition line, was addedsodiumtetraborate decahydrate (3.12 g) and DI water (163 mL). After allsolids were dissolved, isopropylamine (9.63 g) was added. The pH of thebuffer was adjusted to pH 10.5 using 6 N HCl. The buffer was cooled toroom temperature. Then, pyridoxal-5-phosphate (0.33 g) and SEQ ID NO: 1(8.15 g) were added and slowly dissolved at room temperature.

Crude keto ester 19 (23.6 g, 69 wt %, 16.3 g assay, 39 mmol) wasdissolved in DMSO (163 mL) and the solution was added to the reactorover 5-10 min. Then the reaction was heated to 55° C. The pH wasadjusted to 10.5 according to a handheld pH meter and controlledovernight with an automated pH controller using 8 M aqueousisopropylamine. The reaction was aged for 27.5 hours.

After confirmation of >95A % conversion by HPLC, the reaction wasextracted by first adding a mixture of iPA: iPAc (3:4, 350 mL) andstirring for 20 min. The phases were separated and the aqueous layer wasback extracted with a mixture of iPA: iPAc (2:8, 350 mL). The phaseswere separated. The organic layers were combined and washed with DIwater (90 mL). The HPLC based assay yield in the organic layer was 20(9.86 g, 70.5% assay yield) with >60:1 dr at the positions C5 and C6.

tert-Butyl((3S,5S,6R)-6-methyl-2-oxo-5-(2,3,6-trifluorophenyl)piperidin-3-yl)carbamate(21)

A solution of crude cis and trans mixture 20 in a mixture of iPAc andiPA (1.83 wt %, 9.9 kg; 181 g assay as a mixture) was concentrated invacuo and dissolved in 2-Me-THF (3.6 L). To the solution was addedtert-BuOK (66.6 g, 0.594 mol) at room temperature. The suspension wasstirred at room temperature for 2 h. The mixture was poured into water(3.5 L) and the organic layer was separated, washed with 15 wt % ofaqueous NaCl (3.5 L), dried over Na₂SO₄, and concentrated to dryness.The residue was suspended with iPAc (275 mL) and heptane (900 mL) at 60°C. The suspension was slowly cooled down to 1° C. The solid was filteredand rinsed with iPAc and heptane (1:3), dried to afford 21 (166 g, 93 wt%; 85%) as crystals. Mp 176-179° C.; ¹H NMR (CDCl₃, 500 MHz): δ 7.06 (m,1H), 6.84 (m, 1H), 5.83 (broad s, 1H), 5.58 (broad s, 1H), 4.22 (m, 1H),3.88-3.79 (m, 2H), 2.77 (m, 1H), 2.25 (m, 1H), 1.46 (s, 9H), 1.08 (d,J=6.4 Hz, 3H); ¹⁹F NMR (CDCl₃, 376 MHz): δ −117 (d, J=14 Hz), −135 (d,J=20 Hz), −142 (dd, J=20, 14 Hz); ¹³C NMR (CDCl₃, 100 MHz): δ 171.1,156.6 (ddd, J=245, 6.4, 2.8 Hz), 155.8, 149.3 (ddd, J=248, 14.4, 8.8Hz), 147.4 (ddd, J=245, 14.2, 3.8 Hz), 118.0 (dd, J=19.3, 14.5 Hz),115.9 (dd, J=19.2, 10.4 Hz), 111.0 (ddd, J=26.4, 6.0, 4.3 Hz), 79.8,51.4, 49.5, 34.1, 29.3, 28.3, 18.0; HRMS: m/z calcd for C₁₇H₂₁F₃N₂O₃381.1396 (M+Na). found 381.1410.

tert-Butyl((5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)carbamate(22)

To a solution of 21 (10 g, 87% purity, 24.3 mmol) in THF (70 ml) wasadded tert-BuOLi (2.5 g, 31.2 mmol) at 5° C. in one portion. Thesolution was cooled to between 0 and 5° C. and trifluoroethyltrifluoromethanesulfonate (10.0 g, 43 mmol) was added in one portion.DMPU (7 mL) was added slowly over 15 min while maintaining the thereaction temperature below 5° C. After the mixture was stirred at 0° C.for 3 h, additional tert-BuOLi (0.9 g, 11.2 mmol) was added. The mixturewas aged for an additional 90 min. The mixture was quenched with 0.2 NHCl (70 ml), followed by addition of heptane (80 ml). The organic layerwas separated and aqueous layer extracted with heptane (30 ml). Thecombined organic layers were washed with 15% aqueous citric acid (50 mL)and 5% aqueous NaHCO₃ (50 mL). The solution was concentrated undervacuum at 40° C. and the resulting oil was dissolved in iPAc (30 mL).The solution was used directly in the next step without furtherpurification. The HPLC analysis indicated that the solution contained 22(9.8 g, 92% as cis and trans mixture in a ratio of 6.5 to 1) along with4% of starting material 21 and 8% of a N,N′-alkylated compound.Analytically pure 22 (cis isomer) was isolated by chromatography onsilica gel with ethyl acetate and heptane as an eluant. ¹H NMR (CDCl₃,500 MHz): δ 7.15 (m, 1H), 6.85 (m, 1H), 5.45 (broad, s, 1H), 4.90 (m,H), 4.20 (m, 1H), 3.92 (m, 2H), 3.28 (m, 1H), 2.70 (m, 2H), 1.48 (s,9H), 1.20 (d, J=5.9 Hz, 3H); ¹³C NMR (CDCl₃, 100 MHz): δ 170.2, 156.9(ddd, J=245, 6.3, 2.7 Hz), 156.0, 149.6 (ddd, J=251, 14.8, 8.8 Hz),147.6 (ddd, J=246, 13.9, 3.6 Hz), 124.5 (q, J=281 Hz), 117.6 (dd,J=19.2, 3.7 Hz), 116.4 (dd, J=19.1, 10.4 Hz), 111.4 (ddd, J=25.8, 6.4,4.1 Hz), 56.6, 52.8, 45.3 (q, J=34.2 Hz), 35.2, 28.7, 28.3 (br t, J=4Hz), 14.6; HRMS: m/z calcd for C₁₉H₂₂F₆N₂O₃ (M+H): 441.1607. found441.1617.

(3S,5S,6R)-6-Methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-aminium(S)-2-acetamido-3-phenylpropanoate (23)

iPAc solution of 22 (529 g assayed, 1.2 mol), obtained from previousstep, was diluted to 6 L with iPAc, p-toluenesulfonic acid monohydride(343 g, 1.8 mol) was added and the solution was heated to 55° C. After 4h, the reaction completed (>99% conversion). Aqueous K₂CO₃ (530 g in 3 Lof water) was charged into the solution after cooled to 15-25° C. Theaqueous layer was separated and was back-extracted with iPAc (2 L). TheiPAc solutions were combined and the total volume was adjusted to 10 Lby adding iPAc. The solution was heated to 50-60° C. About 20 g ofN-acetyl L-phenylalanine was added and the solution was agitated for 15min or until solids precipitated out. The remaining N-acetylL-phenylalanine (total 250 g, 1.2 mol) was charged slowly and2-hydroxy-5-nitrobenzaldehyde (2 g) was charged. The suspension wasagitated for 12 h at 20° C. and then cooled to 0° C. for 3 h. Thesuspension was filtrated, washed with iPAc three times and dried to give23 (583 g, 89% yield) as crystals. Mp 188-190° C.; ¹H NMR (DMSO-d₆, 400MHz): δ 7.96 (d, J=8.0 Hz, 1H), 7.48 (m, 1H), 7.15-7.25 (m, 6H), 4.65(ddd, J=19.4, 15.3, 9.6 Hz, 1H), 4.33 (ddd, J=8.7, 8.4, 4.9 Hz, 1H),3.70-3.87 (m, 3H), 3.57 (dd, J=11.5, 6.6 Hz, 1H), 3.04 (dd, J=13.7, 4.9Hz, 1H), 2.82 (dd, J=13.7, 8.9 Hz, 1H), 2.59 (m, 1H), 2.24 (m, 1H), 2.95(s, 3H), 1.10 (d, J=6.4 Hz, 1H); ¹⁹F NMR (DMSO-d₆, 376 MHz): δ −69 (s),−118 (d, J=15 Hz), −137 (d, J=21 Hz), −142 (dd, J=21, 15 Hz); ¹³C NMR(DMSO-d₆, 100 MHz): δ 173.6, 171.1, 168.7, 156.3 (ddd, J=243.5, 7.0, 3.1Hz), 148.7 (ddd, J=249, 14.4, 9.1 Hz), 146.8 (ddd, J=245, 13.7, 3.1 Hz),138.5, 129.2, 128.0, 126.1, 124.9 (q, J=280.9 Hz), 117.4.0 (dd, J=19.3,13.8 Hz), 116.7 (dd, J=19.3, 10.6 Hz), 111.8 (ddd, J=26.0, 6.7, 3.6 Hz),56.6, 54.3, 51.2, 44.3 (q, J=32.5 Hz), 37.2, 34.8, 26.9 (br t, J=4 Hz),22.5, 14.1.

(3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-aminium2,2-diphenylacetate (25)

To a mixture of crude material containing(5S,6R)-3-amino-6-methyl-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-2-one(24, 2.00 g, 5.88 mmol), prepared according to the same method as theprevious example, and 3,5-dichloro-2-hydroxybenzaldehyde (0.011 g, 0.059mmol) in isopropyl acetate (15.0 ml) at 55-60° C. under nitrogen wasslowly added a solution of diphenylacetic acid (1.26 g, 5.88 mmol) inTHF (10.0 ml) over 2 h. Upon completion of acid addition, a thick saltsuspension was agitated at 55-60° C. for another 18 h and then wasallowed to cool to ambient temperature. The salt was filtered and washedwith isopropyl acetate. After drying at 60° C. in a vacuum oven withnitrogen purge for 8 hours, 25 (2.97 g, 91.4%) was obtained as crystals.¹H NMR (500 MHz, DMSO-d₆): δ 7.48 (qd, J=9.4, 4.9 Hz, 1H), 7.32 (d,J=7.7 Hz, 4H), 7.25-7.26 (m, 4H), 7.19-7.17 (m, 3H), 6.79 (br, 3H), 4.95(s, 1H), 4.67 (dq, J=15.3, 9.7 Hz, 1H), 3.81-3.79 (m, 3H), 3.62 (dd,J=11.6, 6.5 Hz, 1H), 2.66-2.62 (m, 1H), 2.25 (dd, J=12.9, 6.4 Hz, 1H),1.11 (d, J=6.5 Hz, 3H); ¹³C NMR (100 MHz, DMSO-d₆): δ 174.4, 171.8,156.9 (ddd, J=244, 7.0, 2.5 Hz), 149.1 (ddd, J=249, 14.4, 8.5 Hz), 147.2(ddd, J=246, 13.9, 3.2 Hz), 141.4, 129.0, 128.5, 126.7, 125.5 (q, J=281Hz), 118.0 (dd, J=19.8, 13.8 Hz), 117.1 (dd, J=19.2, 10.6 Hz), 112.3(ddd, J=26.1, 6.7, 3.3 Hz), 58.5, 57.1, 51.7, 44.8 (q, J=32.7 Hz), 35.3,27.5 (br t, J=4.6 Hz), 14.5.

(3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-aminium1H-indole-2-carboxylate (26)

To a mixture of crude material containing 24 (2.00 g, 5.88 mmol) and3,5-dichloro-2-hydroxybenzaldehyde (0.011 g, 0.059 mmol) in isopropylacetate (15.0 ml) at 55-60° C. under nitrogen was slowly added asolution of 1H-indole-2-carboxylic acid (0.96 g, 5.88 mmol) in THF (10.0ml) over 2 hours. Upon completion of acid addition, a thick saltsuspension was agitated at 55-60° C. for another 18 h and then wasallowed to cool to ambient temperature. The salt was filtered and washedwith isopropyl acetate. After drying at 60° C. in a vacuum oven withnitrogen purge for 8 h, 26 (2.33 g, 79.0%) was isolated as crystals. ¹HNMR (500 MHz, DMSO): δ 11.40 (s, 1H), 7.56 (d, J=8.0 Hz, 1H), 7.45 (br,3H), 7.47 (ddd, J=14.8, 10.1, 8.3 Hz, 1H), 7.41-7.40 (m, 1H), 7.16-7.14(m, 2H), 6.98-6.97 (m, 1H), 6.87 (s, 1H), 4.69 (dq, J=15.3, 9.6 Hz, 1H),3.84-3.81 (m, 4H), 2.76-2.71 (m, 1H), 2.34 (dd, J=12.7, 6.3 Hz, 1H),1.13 (d, J=6.5 Hz, 3H); ¹³C NMR (100 MHz, DMSO-d₆): δ 170.9, 164.8,156.8 (ddd, J=244, 7.0, 2.5 Hz), 149.1 (ddd, J=249, 14.4, 8.5 Hz), 147.2(ddd, J=246, 13.9, 3.2 Hz), 137.0, 133.5, 127.8, 125.4 (q, J=282 Hz),123.3, 121.8, 119.7, 117.8 (dd, J=19.8, 13.8 Hz), 117.2 (dd, J=19.2,10.6 Hz), 112.7, 112.3 (ddd, J=26.1, 6.7, 3.3 Hz), 105.1, 57.1, 51.3,44.8 (q, J=32.7 Hz), 35.2, 26.9, 14.5.

N-((3S,5S,6R)-6-Methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemonohydrate (28)

To a suspension of 23 (5.0 g, 9.1 mmol) in isopropyl acetate (50 mL) wasadded 5% aqueous K₃PO₄ (50 mL). The mixture was stirred for 5 min. Theorganic layer was separated and washed with aqueous K₃PO₄ (50 mL).Solvent removed under vacuum and resulting oil (27) was dissolved inacetonitrile (20 mL). To another flask was added 14 (2.57 g),acetonitrile (40 mL), water (20 mL) and NaOH solution (10N, 0.9 mL). Thesolution of 27 in acetonitrile was charged to the mixture followed byHOBT monohydrate (1.5 g) and EDC hydrochloride (2.6 g). The mixture wasagitated at room temperature for 4 h and HPLC analysis indicated acomplete conversion. The reaction mixture was stirred with isopropylacetate (60 mL) and the aqueous layer was removed. The organic layer waswashed with 5% aqueous NaHCO₃ (40 mL) followed by a mixture of 15%aqueous citric acid (40 mL) and saturated aqueous NaCl (10 mL). Theresulting organic layer was finally washed with 5% aqueous NaHCO₃ (40mL). The solvent was removed under vacuum and the residue was dissolvedin methanol (20 mL). The methanol solution was slowly charged into amixture of water (50 mL) and methanol (5 mL) over 30 min with goodagitation, followed by addition of water (50 mL) over 30 min. Thesuspension was stirred over night at room temperature. The mixture wasfiltered and crystals were dried in a vacuum oven for 5 h at 50° C. togive 28 (5.4 g, 95%) as monohydrate. ¹H NMR (500 MHz, CD₃OD): δ 8.88 (t,J=1.2 Hz, 1H), 8.15 (t, J=1.2 Hz, 1H), 8.09 (dd, J=5.3, 1.5 Hz, 1H),7.36 (dd, J=7.4, 1.5 Hz, 1H), 7.28 (qd, J=9.3, 4.7 Hz, 1H), 7.01 (tdd,J=9.7, 3.6, 1.9 Hz, 1H), 6.96 (dd, J=7.4, 5.3 Hz, 1H), 4.80 (dq, J=15.2,9.2 Hz, 1H), 4.56 (dd, J=11.7, 6.8 Hz, 1H), 4.03 (ddd, J=13.6, 4.2, 2.6Hz, 1H), 3.97-3.90 (m, 1H), 3.68 (dq, J=15.3, 8.8 Hz, 1H), 3.59 (t,J=16.2 Hz, 2H), 3.35 (d, J=4.4 Hz, 1H), 3.32 (d, J=3.5 Hz, 1H), 3.21(qt, J=12.7, 3.1 Hz, 1H), 2.38-2.32 (m, 1H), 1.34 (d, J=6.5 Hz, 3H); ¹³CNMR (126 MHz, CD₃OD): δ 182.79, 171.48, 168.03, 166.71, 159.37 (ddd,J=244.1, 6.5, 2.1 Hz), 157.43, 150.88 (ddd, J=249.4, 14.4, 8.7 Hz),148.96 (ddd, J=243.8, 13.7, 3.1 Hz), 148.67, 148.15, 136.84, 133.43,131.63, 130.83, 130.48, 126.41 (q, J=280.0 Hz), 119.85, 118.89 (dd,J=19.0, 13.5 Hz), 117.77 (dd, J=19.8, 10.8 Hz), 112.80 (ddd, J=26.5,6.5, 4.2 Hz), 58.86, 53.67, 52.87, 46.56 (q, J=33.3 Hz), 45.18, 42.06,36.95, 27.76 (t, J=4.8 Hz), 14.11.

Example 3 3-Hydroxy-3-(2,3,6-trifluorophenyl)butan-2-one (30)

To a solution of 1,2,4-trifluorobenzene (29, 49.00 g, 371 mmol) anddiisopropylamine (4.23 mL, 29.7 mmol) in THF (750 mL) at −70° C. wasslowly added 2.5 M of n-BuLi (156.0 ml, 390 mmol) to maintaintemperature between −45 to −40° C. The batch was agitated for 30 min. Toanother flask, a solution of 2,3-butadione (37.7 mL, 427 mmol) in THF(150 mL) was prepared and cooled to −70° C. The previously preparedlithium trifluorobenzene solution was transferred to the second flaskbetween −70 to −45° C. The reaction was agitated for 1 hour at −55 to−45 and then quenched by adding AcOH (25.7 mL, 445 mmol) and then water(150 mL). After warmed to room temperature, the aqueous layer wasseparated. The aqueous solution was extracted with MTBE (200 mL×1) andthe combined organic layers were washed with brine (100 mL×1). Theorganic layer was concentrated at 25-35° C. The residue was flashed withheptane (100 mL×1) and concentrated to dryness and give 30 (87.94 g,90.2 wt %, 98% yield, and >99% HPLC purity) as an oil. ¹H NMR (CDCl₃,400 MHz): δ 7.16 (m, 1H), 6.86 (m, 1H), 6.88 (s, 1H), 4.59 (s, 1H), 2.22(s, 3H), 1.84 (dd, J=4.0, 2.8 Hz, 3H); ¹⁹F NMR (CDCl₃, 376.6 MHz): δ−114.6 (dd, J=14.5, 1.4 Hz), −133.6 (d, J=19.9 Hz), −141.3 (dd, J=19.9,14.5 Hz); ¹³C NMR (CDCl₃, 100 MHz): δ 207.4, 156.4 (ddd, J=247, 6.2, 2.9Hz), 149.4 (ddd, J=253, 15.0, 9.0 Hz), 147.5 (ddd, J=245, 14.4, 3.3 Hz),119.4 (dd, J=17.3, 11.7 Hz), 117.0 (ddd, J=19.3, 11.1, 1.4 Hz), 116.6(ddd, J=26.6, 6.5, 4.1 Hz), 77.9, 25.0 (dd, J=6.5, 4.9 Hz), 23.3.

3-(2,3,6-Trifluorophenyl)but-3-en-2-one (31)

The hydroxy ketone 30 (7.69 g, 35.2 mmol) and 95% H₂SO₄ (26.2 mL, 492.8mmol) were pumped at 2.3 and 9.2 mL/min respectively into the flowreactor. The temperature on mixing was controlled at 22-25° C. byplacing the reactor in a water bath (21° C.). The effluent was quenchedinto a a mixture of cold water (106 g) and heptane/IPAc (1:1, 92 mL) ina jacketed reactor cooled at 0° C.; the internal temperature of thequench solution was ˜7° C. during the reaction. The layers in the quenchreactor were separated and the organic layer was washed with 10%NaH₂PO₄/Na₂HPO₄ (1:1, 50 mL). The pH of the final wash was 5-6. Solkaflock (3.85 g, 50 wt %) was added to the organic solution. The resultingslurry was concentrated and solvent-switched to heptanes at 25-30° C.The mixture was filtered, rinsed with heptanes (50 mL×1). The combinedfiltrates were concentrated under vacuum to give 31 as an light yellowoil (6.86 g, 90 wt %, 87% yield), which solidified in a freezer. ¹H NMR(CDCl₃, 400 MHz): δ 7.13 (m, 1H), 6.86 (m, 1H), 6.60 (s, 1H), 6.15 (s,1H), 2.46 (s, 3H); ¹⁹F NMR (CDCl₃, 376.6 MHz): δ −117.7 (dd, J=15.0, 1.4Hz), −135.4 (dd, J=21.4, 1.4 Hz), −42.7 (dd, J=21.4, 15.0 Hz); ¹³C NMR(CDCl₃, 100 MHz): δ 196.3, 155.3 (ddd, J=245, 5.1, 2.9 Hz), 147.9 (ddd,J=250, 14.5, 7.8 Hz), 147.0 (ddd, J=245, 13.4, 3.7 Hz), 137.5 (d, J=1.3Hz), 131.7, 116.6 (ddd, J=19.9, 9.7, 1.2 Hz), 116.2 (dd, J=22.6, 16.5Hz), 110.6 (ddd, J=24.8, 6.5, 4.1 Hz), 25.8.

Alternative Synthesis of 3-(2,3,6-trifluorophenyl)but-3-en-2-one (31)

A solution of 18 (3.5 g, 18.6 mmol), acetic acid (0.34 ml, 5.58 mmol),piperidine (0.37 ml, 3.72 mmol), formaldehyde (6.0 g, 37% aqueoussolution) in MeCN (20 mL) was heated over weekend. The conversion wasabout 60%. Reaction was heated to 70° C. overnight. The mixture wasconcentrated and extracted with MTBE and HCl (0.5N). The organic layerwas washed with aqueous K₂CO₃ (0.5N) and water, in turns. The organiclayer was concentrated. The product was isolated by chromatographycolumn (hexane and EtOAc), yielding 31 (2.29 g, 61.5%).

Isopropyl2-((diphenylmethylene)amino)-5-oxo-4-(2,3,6-trifluorophenyl)hexanoate(32)

Diphenylidene isopropyl glycinate (2.0 g, 7.0 mmol) and 31 (1.4 g, 7.0mmole) were dissolved in THF (10 ml). The solution was cooled to −10° C.tert-BuOLi (0.56 g, 7.0 mmole) was charged into the solution in severalportions. The reaction was warmed up to room temperature slowly andstirred overnight. After quenched by addition of aqueous NH₄Cl, thesolvents were removed by distillation under vacuum. The residue wassubjected to silica chromatography column eluted by hexane and EtOAcyielding 32 (3.0 g, 89%) as an oil, which was directly used in the nextstep.

Isopropyl2-((tert-butoxycarbonyl)amino)-5-oxo-4-(2,3,6-trifluorophenyl)hexanoate(19)

Compound 32 (100 mg, 0.21 mmol) was dissolved in THF (2 ml) and thesolution was cooled to −10° C. Hydrochloric acid (2N, 1 ml) was addedand stirred until all starting material disappeared by TLC. The pH ofthe reaction was adjusted (pH.>10) by addition of aqueous K₂CO₃. Boc₂O(68 mg, 0.31 mmole) was added into the mixture and stirred overnight.The reaction was completed checked by TLC and the product was identicalto the one prepared from the iodo coupling route.

Isopropyl2-((tert-butoxycarbonyl)amino)-5-oxo-4-(2,3,6-trifluorophenyl)hexanoate(19)

To a 100 mL round bottom was charged 2-methyl THF (43.7 mL) anddiisopropyl amine (4.92 mL, 34.2 mmol) and the solution was cooled to−70° C. n-BuLi (13.08 mL, 32.7 mmol) was charged dropwise during whichthe temperature was controlled below −45° C. The mixture was stirred at−45° C. for 0.5 h. N-Boc-glycine ester (3.58 g) was added dropwisekeeping temperature between −45 to −40° C. and aged at the sametemperature for 1 h.

The solution of 31 (2.91 g, 14.5 mmol) in 2-methyl THF (2.9 mL) was thenadded dropwise in the same manner at −45 to −40° C. After a 0.5-1 h age,LC analysis showed nearly complete reaction. The reaction was quenchedby addition of HOAc (3.83 mL) and the mixture was warmed to −10° C. andwater (11.6 mL, 4 vol) was charged at <20° C. The phase was separated,and the organic layer was washed with 16% NaCl aqueous solution (11.6mL). Assay desired product 19 as a mixture of diastereomers in theorganic solution was 5.40 g (89% yield). The organic layer wasconcentrated to give crude product 19, which was directly used in thenext step reaction. For characterization purposes, a small sample waspurified by flash chromatography (silica gel, EtOAc/hexanes=1:10) togive two diastereomers 19A and 19B. 19A as a colorless oil, ¹H NMR(CD₃CN, 400 MHz) δ: 7.29 (m, 1H), 7.02 (m, 1H), 5.58 (d, J=6.1 Hz, 1H),4.91 (m, 1H), 4.19-4.05 (m, 2H), 2.79 (m, 1H), 2.05 (s, 3H), 1.84 (m,1H), 1.41 (s, 9H), 1.23 (d, J=6.7 Hz, 3H), 1.22 (d, J=6.7 Hz, 3H); ¹³CNMR (CD₃CN, 100 MHz) δ: 204.7, 172.4, 158.6 (ddd, J=244, 6, 3 Hz),156.3, 149.8 (ddd, J=248, 15, 9 Hz), 148.5 (ddd, J=242, 14, 3 Hz), 118.3(dd, J=21, 16 Hz), 117.7 (ddd, J=19, 10, 2 Hz), 112.6 (ddd, J=26, 7, 4Hz), 80.2, 70.0, 53.5, 46.0, 32.0, 28.5, 22.0, 21.9. 19B as colorlesscrystals, MP 91.5-92.0° C., ¹H NMR (CD₃CN, 400 MHz) δ: 7.31 (m, 1H),7.03 (m, 1H), 5.61 (d, J=8.2 Hz, 1H), 4.95 (m, 1H), 4.19 (dd, J=10.2,5.1 Hz, 1H), 3.72 (m, 1H), 2.45-2.29 (m, 2H), 2.09 (s, 3H), 1.41 (s,9H), 1.21 (d, J=6.3 Hz, 3H), 1.20 (d, J=6.3 Hz, 3H); ¹³C NMR (CD₃CN, 100MHz) δ: 205.0, 172.8, 157.9 (ddd, J=244, 7, 3 Hz), 156.5, 150.3 (ddd,J=248, 149, 9 Hz), 148.5 (ddd, J=242, 13, 4 Hz), 117.9 (dd, J=19, 10Hz), 115.9 (dd, J=21, 15 Hz), 111.5 (ddd, J=25, 8, 4 Hz), 80.1, 69.9,52.9, 46.5, 31.1, 28.5, 22.0, 21.9.

Example 4 N-Methoxy-N-methyl-2-(o-tolyl)acetamide (34)

To a solution of NHMe(OMe).HCl (203 g, 2.1 mol) in THF (1 L), H₂O (400mL) and TEA (263 g, 2.2 mol) was added 33 (200 g, 1.3 mol) and CDI (243g, 1.5 mol) at 0-10° C. The reaction mixture was stirred at 0-10° C. for5 h. After HPLC showed that the reaction was complete, the mixture wasfiltered through celite and the filtrate was partitioned with water andEtOAc. The organic solution was dried over Na₂SO₄ and concentrated. Thecrude residual was further purified by flash chromatography on silicagel (5-10% EtOAc/PE) to give 34 (200 g, 78% yield). ¹H NMR (CDCl₃, 400MHz): δ 7.17-7.13 (m, 4H), 3.75 (m, 2H), 3.66 (d, 3H), 3.11 (s, 3H),2.20 (s, 3H), 1.63-1.55 (m, 1H); MS (ESI) m/e [M+H]⁺: 194.1.

1-(o-Tolyl)propan-2-one (35)

A solution of CeCl₃ (114.4 g, 0.45 mol) in THF (4 L) was degassed for 1h and heated to 45-50° C. for 5 h. When the solution was cooled to−10˜−5° C., MeMgCl (193.2 g, 2.6 mol) in THF was added and the mixturewas stirred for 1 h at −10˜−5° C. After amide 34 (256 g, 1.3 mol) wascharged into the reaction mixture at −10˜−5° C., the mixture was stirredfor 5 h at 10-20° C. After the reaction was complete monitored by LCMS,the mixture was quenched by 1M HCl, and then partitioned with water andEtOAc. The organic phase was dried over Na₂SO₄ and concentrated. Thecrude residual was further purified by flash chromatography on silicagel (2-10% EtOAc/PE) to give 35 (157 g, 80% yield). ¹H NMR (CDCl₃, 400MHz): δ 7.1-6.91 (d, 4H), 3.55 (s, 3H), 2.25 (s, 3H), 2.05 (s, 3H); MS(ESI) m/e [M+H]⁺: 149.05.

Isopropyl 2-((tert-butoxycarbonyl)amino)-5-oxo-4-(o-tolyl)hexanoate (36)

To a solution of 2 (181.2 g, 0.557 mol) in THF (1 L) was added TEA (84.6g, 0.836 mol) in portions at 15-20° C. The mixture was stirred for 30 h.After the reaction was complete, the solution was concentrated to givecrude 7. To a solution of 35 (82.5 g, 0.557 mol) and Cs₂CO₃ (91 g, 0.279mol) in DMSO (1 L) was added slowly crude 7 in DMSO (500 mL) over 30 minat 15-20° C. The mixture was stirred for 1 h. After the reaction wascomplete, the mixture was partitioned with water and MTBE (5 L), andextracted with MTBE twice. The combined organic layer was dried overNa₂SO₄ and concentrated. The crude residual was further purified byflash chromatography on silica gel (5-10% EtOAc/PE) to give 36 (138 g,65% yield). ¹H NMR (DMSO-d₆, 400 MHz): δ 7.14-7.09 (m, 3H), 7.10-6.91(d, 1H), 4.93-4.89 (m, 1H), 4.05-3.98 (s, 3H), 2.39-2.37 (d, 3H),1.98-1.92 (d, 3H), 1.20-1.19 (m, 9H), 1.18-1.15 (m, 6H); MS (ESI) m/e[M+H]⁺: 364.2

tert-Butyl((5S,6R)-6-methyl-2-oxo-5-(o-tolyl)piperidin-3-yl)carbamate(37)

To a solution of NaBO₃.4H₂O (10 g, 0.026 mol) in H₂O (180 g) was chargedisopropylamine (30 g, 0.25 mmol) dropwise at 20° C. After the mixturewas stirred for 30 min, the pH was adjusted to 10.3-10.5 by 6M HCl. PLP(1 g, 6.4 mmol) and ATA-412 (25 g) was charged to the solution at 20° C.After the above mixture was stirred for 1 h, a solution of 36 (50 g, 4.7mmoL) in DMSO (250 mL) was added slowly at 20° C. The solution washeated to 55° C. and stirred for 24 h. After the reaction was complete,the reaction was quenched by isopropyl alcohol (100 mL), and thenpartitioned with water and IPAc. The organic phase was dried over Na₂SO₄and concentrated. The crude residual was further purified by flashchromatography on silica gel (5-20% EtOAc/PE) to give 37 (16.5 g, 40%yield). ¹H (DMSO-d₆, 400 MHz): δ 7.83 (s, 1H), 7.18-7.13 (m, 4H), 4.06(br, 1H), 3.67-3.51 (m, 2H), 2.30 (d, 3H), 1.99 (t, 1H), 1.36 (s, 9H),0.82 (m, 3H); MS (ESI) m/e [M+H]⁺: 319.2

tert-Butyl((5S,6R)-6-methyl-2-oxo-5-(o-tolyl)-1-(2,2,2-trifluoroethyl)piperidin-3-yl)carbamate(38)

To a solution of 37 (50 g, 0.164 mol) and DMPU (25 g, 0.2 mol) in THF(500 mL) was added tert-BuOLi (16.5 g, 0.2 mol) in portions at 20° C.for 0.5 h. After the mixture was degassed for 30 min at 20° C.,CF₃CH₂OTf (45.8 g, 0.2 mol) was added at 20-25° C. The reaction wasstirred for 24 h at 20-25° C. After the reaction was complete, themixture was quenched by water, and then partitioned with water andEtOAc. The organic solution was dried over Na₂SO₄ and concentrated. Thecrude residual was further purified by flash chromatography on silicagel (2-10% EtOAc/PE) to give product 38 (50 g, 78% yield). ¹H NMR(DMSO-d₆, 400 MHz): δ 7.18-7.13 (m, 4H), 4.17 (m, 1H), 4.11 (br, 1H),3.67 (m, 3H), 2.66 (s, 1H), 2.33 (d, 3H), 1.83 (t, 1H), 1.41 (s, 9H),0.96 (d, 3H); MS (ESI) m/e [M+H]⁺ 405.17.

(3S,5S,6R)-6-Methyl-2-oxo-5-(o-tolyl)-1-(2,2,2-trifluoroethyl)piperidin-3-aminium4-methylbenzoate (39)

To a solution of 38 (2.0 g, 5.0 mol) in THF (10 mL) was added 6N HCl (10mL, 59.9 mmol) dropwise. The reaction was aged at 20-25° C. for 5 h thenconcentrated to remove THE. The residue was diluted with MTBE andbasified with K₂CO₃. A total of 3 mL of H₂O was added to dissolve allsolids. The organic layer was separated, washed with brine, andsolvent-switched to IPAC. To one-third of the organic layer was added4-methylbenzoic acid (0.27 g, 2.00 mmol). The solution was heated to 50°C. and 2-hydroxy-5-nitrobenzaldehyde (0.0028 g, 0.017 mmol) was added.The reaction was aged at 20-25° C. for 16 h. The resulting slurry waschilled in an ice bath to 2° C. and filtered. The solids were washedwith IPAC and dried to give product 39 (0.38 g, 52%) as crystals. ¹H NMR(500 MHz, DMSO-d₆): δ 7.82 (d, J=8.0 Hz, 2H), 7.26 (d, J=7.9 Hz, 2H),7.18-7.19 (m, 3H), 7.12 (d, J=7.5 Hz, 1H), 4.67 (dq, J=15.2, 9.7 Hz,1H), 3.72-3.74 (m, 2H), 3.61-3.63 (m, 1H), 3.55 (dd, J=11.3, 6.7 Hz,1H), 2.40 (dd, J=25.2, 12.9 Hz, 1H), 2.35 (s, 3H), 2.32 (s, 3H), 2.02(dd, J=12.6, 6.7 Hz, 1H), 0.91 (d, J=6.4 Hz; 3H); ¹³C NMR (100 MHz,DMSO-d₆): δ 172.7, 168.3, 142.4, 139.1, 136.1, 130.9, 130.5, 129.7,129.3, 127.4, 127.2, 126.5, 125.6 (q, J=281 Hz), 56.2, 52.1, 45.0 (q,J=32.3 Hz), 38.5, 29.1, 21.5, 18.7, 14.2

(S)—N-((3S,5S,6R)-6-Methyl-2-oxo-5-(o-tolyl)-1-(2,2,2-trifluoroethyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamide(41)

Salt 39 (0.25 g, 0.58 mmol) was partitioned between IPAC (2.5 mL) and 5wt % aqueous solution of K₃PO₄ (2.5 mL), and washed twice with 5 wt %aqueous K₃PO₄. The organic layer was washed with brine, dried overNa₂SO₄ and concentrated to give a crude 40. Crude 40 was dissolved inMeCN (1.75 mL) and H₂O (1.0 mL). To this was added acid 14 (0.17 g, 0.53mmol), HOBT (0.11 g, 0.70 mmol) and EDC.HCl (0.17 g, 0.87 mmol). Theheterogeneous mixture was aged at 20-25° C. for 16 h. The homogeneousreaction was partitioned between IPAC and saturated aqueous NaHCO₃, andwashed twice with saturated aqueous NaHCO₃. The organic layer was washedwith 15 wt % aqueous citric acid solution, saturated aqueous NaHCO₃ andbrine. The organic layer was dried over Na₂SO₄ and concentrated to giveproduct 41 (0.29 g, 89% yield). ¹H NMR (400 MHz, CD₃OD): δ 8.88 (d,J=1.9 Hz, 1H), 8.15 (d, J=1.9 Hz, 1H), 8.08 (dd, J=5.3, 1.6 Hz, 1H),7.35 (dd, J=7.4, 1.6 Hz, 1H), 7.15-7.18 (m, 4H), 6.95 (dd, J=7.4, 5.3Hz, 1H), 4.59 (dd, J=11.5, 7.0 Hz, 1H), 3.89-3.92 (m, 1H), 3.81 (dt,J=13.4, 3.2 Hz, 1H), 3.61-3.63 (m, 4H), 3.31-3.32 (m, 2H), 2.93-2.95 (m,1H), 2.40 (s, 3H), 2.14-2.17 (m, 1H); 1.14 (d, J=6.5 Hz, 3H); ¹H NMR(500 MHz, CDCl₃): δ 8.91 (s, 1H), 8.56 (s, 1H), 8.17 (dd, J=5.0, 1.5 Hz,1H), 8.05 (s, 1H), 7.30 (d, J=5.0 Hz, 1H), 7.20 (m, 3H), 7.12 (m, 2H),6.89 (dd, J=7.5, 5.0 Hz, 1H), 5.00-4.94 (m, 1H), 4.55 (m, 1H), 3.93-3.90(m, 1H), 3.81-3.76 (m, 2H), 3.68 (d, J=16.5 Hz, 1H), 3.31-3.23 (m, 2H),3.17 (d, J=16.5 Hz, 1H), 2.75-2.67 (m, 2H), 2.41 (s, 3H), 1.11 (d, J=6.5Hz, 3H); ¹³C NMR (100 MHz, CD₃OD): δ 182.8, 171.8, 168.0, 166.7, 157.5,148.7, 148.2, 139.5, 137.5, 136.8, 133.4, 132.0, 131.6, 130.8, 130.6,128.4, 128.3, 127.4, 126.6 (q, J=283 Hz), 119.9, 58.1, 53.7, 53.0, 46.7(q, J=33.4 Hz), 45.2, 42.1, 40.2, 28.8, 19.0, 13.6; HRMS: m/z=564.2219(M+1), calculated m/z=564.2234 for C₃₀H₂₈F₃N₅O₃.

Example 5 N-Methoxy-N-methyl-2-(2,3,5-trifluorophenyl)acetamide (43)

To a solution of NHMe(OMe).Cl (20.3 g, 0.21 mol) in THF (110 mL), H₂O(40 mL) and TEA (26.3 g, 0.22 mol) was added 2,3,5-trifluorophenylaceticacid (42, 24.7 g, 0.13 mol) and CDI (24.3 g, 0.15 mol) at 0-10° C. Thereaction mixture was stirred at 0-10° C. for 5 h. After HPLC showed thatthe reaction was complete, the mixture was filtered through celite andthe filtrate was partitioned with water and EtOAc. The organic solutionwas dried over Na₂SO₄ and concentrated. The crude residual was furtherpurified by flash chromatography on silica gel (5-10% EtOAc/PE) to give43 (24.0 g, 80% yield). ¹H NMR (CDCl₃, 400 MHz): δ 6.76-6.72 (m, 2H),3.72 (m, 2H), 3.66 (d, 3H), 3.15 (d, 3H); MS (ESI) m/e [M+H]⁺: 234.07.

1-(2,3,5-Trifluorophenyl)propan-2-one (44)

A solution of CeCl₃ (11.44 g, 0.045 mol) in THF (350 mL) was degassedfor 1 h and heated to 45-50° C. for 5 h. When the solution was cooled to−10˜5° C., MeMgCl (19.44 g, 0.26 mol) in THF was added and the mixturewas stirred for 1 h at −10˜−5° C. After amide 43 (30.3 g, 0.13 mol) wascharged into the reaction mixture at −10˜−5° C., the mixture was stirredfor 5 h at 10-20° C. After the reaction was complete, the mixture wasquenched by 1M HCl, and then partitioned with water and EtOAc. Theorganic phase was dried over Na₂SO₄ and concentrated. The crude residualwas further purified by flash chromatography on silica gel (2-10%EtOAc/PE) to give 44 (20.8 g, 85% yield). ¹H NMR (CDCl₃, 400 MHz): δ6.91-6.78 (m, 1H), 6.69 (dd, 1H), 3.77 (d, 2H), 2.25 (s, 3H); MS (ESI)m/e [M+H]⁺:189.05.

Isopropyl2-((tert-butoxycarbonyl)amino)-5-oxo-4-(2,3,5-trifluorophenyl)hexanoate(45)

To a solution of 2 (10.98 g, 33.7 mmol) in THF (50 mL) was added TEA(4.8 g, 47.4 mmol) in portions at 15-20° C. The mixture was stirred for30 h. After the reaction was complete, the solution was concentrated togive crude 7. To a solution of 44 (6.3 g, 33.7 mmol) and Cs₂CO₃ (5.0 g,15.3 mmol) in DMSO (35 mL) was added slowly crude 7 in DMSO (35 mL) over30 min at 15-20° C. The mixture was stirred for 1 h. After the reactionwas complete, the mixture was partitioned with water and MTBE (50 mL)and extracted twice by MTBE. The combined organic layer was dried overNa₂SO₄ and concentrated. The crude residual was further purified byflash chromatography on silica gel (5-10% EtOAc/PE) to 45 (8.4 g, 60%yield). ¹H NMR (DMSO-d₆, 400 MHz): δ 6.77 (d, 1H), 6.59 (d, 1H), 5.11(m, 1H), 4.93-4.89 (m, 1H), 4.12 (s, 2H), 2.66 (d, 1H), 2.05-2.01 (d,3H), 1.38 (m, 9H), 1.18-1.15 (m, 6H); MS (ESI) m/e [M+H]⁺: 418.18.

tert-Butyl((5S,6R)-6-methyl-2-oxo-5-(2,3,5-trifluorophenyl)piperidin-3-yl)carbamate(46)

To a solution of NaBO₃.4H₂O (1.5 g, 3.9 mmol) in H₂O (18.2 g) wascharged isopropylamine (1.16 g, 19.6 mmol) dropwise at 20° C. After themixture was stirred for 30 min, the pH was adjusted to 10.2-10.3 by 6NHCl. PLP (0.042 g, 0.27 mmol) and ATA-412 (1.0 g) was charged to thesolution at 20° C. After the above mixture was stirred for 1 h, asolution of 45 (2 g, 4.7 mmoL) in DMSO (10 mL) was added slowly at 20°C. The solution was heated to 55° C. and stirred for 24 h. After thereaction was complete, the reaction was quenched by isopropyl alcohol(10 mL), and then partitioned with water and IPAc. The organic solutionwas dried over Na₂SO₄ and concentrated. The crude residual was furtherpurified by flash chromatography on silica gel (5-20% EtOAc/PE) to give46 (1.45 g, 85% yield). ¹H NMR (DMSO-d₆, 400 MHz): δ 7.95-7.78 (m, 1H),6.95 (m, 1H), 3.01 (t, 1H), 1.36 (s, 9H), 1.17-1.10 (br, 4H), 1.12 (m,3H); MS (ESI) m/e [M+H]⁺: 359.15.

tert-Butyl((5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,5-trifluorophenyl)piperidin-3-yl)carbamate(47)

To a solution of 46 (50 g, 0.14 mol) and DMPU (7.2 g, 0.06 mol) in THF(500 mL) was added tert-BuOLi (8.6 g, 0.11 mol) in portions at 20° C.for 0.5 h. After the mixture was degassed for 30 min at 20° C.,CF₃CH₂OTf (37.5 g, 0.14 mol) was added at 20-25° C. The solution wasstirred for 24 h at 20-25° C. After the reaction was complete, themixture was quenched by water, and then partitioned with water andEtOAc. The organic solution was dried over Na₂SO₄ and concentrated. Thecrude residual was further purified by flash chromatography on silicagel (2-10% EtOAc/PE) to give product 47 (50 g, 82% yield). ¹H (DMSO-d₆,400 MHz): δ 7.52 (m, 1H), 7.22-6.91 (m, 1H), 4.65 (m, 1H), 3.85 (br,1H), 3.38-3.37 (m, 2H), 1.40 (s, 9H), 0.90 (m, 3H); MS (ESI) m/e [M+H]⁺:441.15.

(5S,6R)-3-Amino-6-methyl-1-(2,2,2-trifluoroethyl)-5-(2,3,5-trifluorophenyl)piperidin-2-one(48)

To a solution of 47 (2.0 g, 4.5 mmol) in IPAC (20 mL) was addedp-toluenesulfonic acid monohydrate (1.3 g, 6.8 mmol). The mixture wasaged at 55° C. for 4 h. After the reaction was complete, the slurry wascooled in an ice bath to 5° C. and a solution of potassium carbonate(1.9 g, 13.6 mmol) in H₂O (10 mL) was added. The aqueous layer (pH=10)was separated and the organic layer was washed with saturated aqueousNaHCO₃, water and brine, in turns, and dried over Na₂SO₄. Concentrationafforded 48 (1.3 g, 86% yield) as a 4:1 mixture of diastereomers.

(3S,5S,6R)-3-Amino-6-methyl-1-(2,2,2-trifluoroethyl)-5-(2,3,5-trifluorophenyl)piperidin-2-one(S)-2-hydroxysuccinate (49)

To a solution of 48 (0.24 g, 0.72 mmol) in THF (3.7 mL) was addedL-(−)-malic acid (0.10 g, 0.75 mmol). The homogeneous reaction washeated to 58° C. and aged for 3 h. After the reaction was complete, theslurry was cooled to 20-25° C. and aged for 16 h. The solids werefiltered, washed twice with ice-cold THF, and dried to give product 49(0.25 g, 73% yield) as crystals. ¹H NMR (400 MHz, DMSO-d₆): δ 7.50-7.54(m, 1H), 7.01-7.06 (m, 1H), 4.68 (dq, J=15.3, 9.6 Hz, 1H), 4.05 (dd,J=11.6, 6.7 Hz, 1H), 3.91-3.92 (m, 2H), 3.84-3.87 (m, 2H), 2.51 (m, 1H),2.45 (m, 1H), 2.33 (dd, J=15.6, 4.4 Hz, 1H), 2.15 (dd, J=12.3, 6.7 Hz,1H), 0.97 (d, J=6.4 Hz, 3H); ¹³C NMR (100 MHz, DSMO-d₆): δ 176.3, 172.0,168.4, 157.4 (ddd, J=243, 11, 2 Hz), 150.0 (dt, J=248, 14 Hz), 144.7(ddd, J=242, 13, 4 Hz), 130.4 (dd, J=13, 9 Hz), 124.8 (q, J=281 Hz),110.9 (dt, J=26, 3 Hz), 105.1 (dd, J=28, 21 Hz), 66.1, 56.0, 49.6, 44.5(q, J=33 Hz), 41.3, 35.1, 25.1, 13.8; ¹⁹F NMR (377 MHz, DMSO-d₆): δ−69.3, −114.6 (d, J=14.9 Hz), −134.7 (d, J=21.8 Hz), −148.8 (dd, J=21.8,14.9 Hz).

(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,5-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamide(51)

Salt 49 (0.60 g, 1.27 mmol) was partitioned in IPAC (6 mL) and a 5 wt %aqueous K₃PO₄ (6 mL), and washed twice with 5 wt % aqueous K₃PO₄. Theorganic layer was washed with brine, dried with Na₂SO₄ and concentratedto give crude 50. Crude 50 was then dissolved in MeCN (4.2 mL) and H₂O(2.4 mL). To this solution was added acid 14 (0.32 g, 1.12 mmol), HOBT(0.22 g, 1.42 mmol) and EDC.HCl (0.34 g, 1.77 mmol). The heterogeneousmixture was aged at 20-25° C. for 16 h. The reaction was partitionedbetween IPAC and saturated aqueous NaHCO₃, and washed twice withsaturated aqueous NaHCO₃. The organic layer was then washed with 5 wt %aqueous citric acid, saturated aqueous NaHCO₃, and brine. The organiclayer was dried over Na₂SO₄ and concentrated to give product 51.Compound 51 was crystallized from ethanol solution by addition of water.¹H NMR (500 MHz, CD₃OD): δ 9.15 (s, 1H), 8.82 (s, 1H), 8.22 (dd, J=6.1,1.2 Hz, 1H), 8.13 (dd, J=7.3, 1.2 Hz, 1H), 7.37 (dd, J=7.3, 6.1 Hz, 1H),7.16 (m, 1H), 6.94 (m, 1H), 4.79 (m, 1H), 4.67 (dd, J=11.5, 7.1 Hz, 1H),4.06 (m, 1H), 4.01 (d, J=14.2 Hz, 1H), 3.90 (s, 2H), 3.79 (d, J=18.3 Hz,1H), 3.73 (m, 1H), 3.69 (d, J=16.6 Hz, 1H), 2.89 (q, J=12.5 Hz, 1H),2.28 (m, 1H), 1.20 (d, J=6.4 Hz, 3H); ¹³C NMR (400 MHz, CD₃OD): δ 182.8,171.4, 168.1, 166.7, 159.6 (ddd, J=245, 10.5, 2.8 Hz), 157.5, 151.9 (dt,J=250, 14.2 Hz), 148.7, 148.2, 146.9 (ddd, J=243, 12.6, 3.9 Hz), 136.8,133.4, 132.3 (dd, J=13.5, 8.5 Hz), 131.6, 130.8, 130.6, 126.4 (q, J=280Hz), 119.8, 111.7 (bd, J=24.8 Hz), 105.7 (dd, J=28.1, 21.8 Hz), 69.2,58.0, 53.7, 52.5, 46.7 (q, J=33.6 Hz), 45.2, 42.1, 37.5, 27.6, 13.7; ¹⁹FNMR (400 MHz, CD₃OD): δ −71.96, −116.67 (d, J=14.7 Hz), −136.41 (d,J=20.0 Hz), −150.47 (dd, J=19.5, 15.2 Hz); HRMS: m/z=604.1778 (M+1),calculated m/z=604.1778 for C₂₉H₂₄F₆N₅O₃.

Example 6

(2-Bromo-5-chloropyridin-3-yl)methanol (52)

To a solution of 2,3-dibromo-5-chloropyridine (60 g, 221 mmol) in THF(500 mL) was added a solution of isopropylmagnesium chloride lithiumchloride solution in THF (1.3M, 185 mL) at −40° C. over about 30 min.The solution was stirred for 30 min at −40° C. and DMF (50 mL) wasadded. The resulting solution was warmed up to room temperature andstirred for 30 min. The reaction was quenched with 1 N HCl (400 mL) andMTBE (200 mL) was added. Organic layer was separated and washed twicewith 5% aqueous NaHCO₃ (200 mL). The solvent was removed under vacuum at50° C. The resulting solids (aldehyde intermediate) were dissolved inmethanol (400 mL). The solution was cooled to 5° C. under an ice bath.NaBH₄ (3.6 g) was added slowly over 30 min while maintaining thereaction temperature below room temperature. The reaction mixture wasstirred for another 30 min followed by addition of water (125 mL). Theresulting mixture was concentrated under vacuum to approximately 150 ml.Solids precipitated during the concentration. The suspension was stirredvigorously at room temperature for 1 h and solids were collected byfiltration. The wet cake was dried in a vacuum oven over night at 60° C.to give 52 (45.6 g, 93%) as a solid. ¹H NMR (CDCl₃, 400 MHz): δ 8.26 (d,J=2.5 Hz, 1H), 7.88 (d, J=2.5 Hz, 1H), 4.73 (d, J=5.8 Hz, 2H), 2.33 (t,J=11.4 Hz, 1H); ¹³C NMR (CDCl₃, 100 MHz): δ 147.12, 138.48, 138.39,136.14, 132.06, 62.76.

5-Chloro-3-(((tetrahydro-2H-pyran-2-yl)oxy)methyl)picolinaldehyde (53)

To a solution of 52 (5.0 g, 22.5 mmol) in 2-MeTHF (15 mL) was added3,4-dihydro-2H-pyran (2.7 mL, 29.6 mmol) and concentrated sulfuric acid(125 mg) at room temperature. The solution was stirred for 10 min andwas then cooled to −3° C. Isopropylmagnesium chloride lithium chloridesolution (1.3 M, 30 ml, 39 mmol) was slowly added at −3 to 3° C. Theresulting solution was stirred at −3° C. for 3 h until a HPLC showed theconversion was greater than 97%. DMF (5 ml) was added over 15 min below5° C. The resulting solution was stirred for another 1 h at thistemperature. The reaction mixture was quenched by addition of MTBE (50mL), 15% aqueous citric acid (25 mL) and water (15 mL). The organiclayer was separated and washed with 5% aqueous NaCl (50 mL) twice. Theorganic solution was concentrated under vacuum at 50° C. to give 53 asan oil (6.2 g, 68 wt %, 16.6 mmol, 74% yield). The crude product wasused directly for the next step without further purification. The puresample was isolated by flash chromatography on silica gel with 5% ethylacetate in hexane as eluants. ¹H NMR (CDCl₃, 400 MHz): δ 10.13 (s, 1H),8.65 (s, 1H), 8.20 (s, 1H), 5.25 (d, J=16.6 Hz, 1H), 5.01 (d, J=16.6 Hz,1H), 4.80 (m, 1H), 3.88 (m, 1H), 3.58 (m, 1H), 1.7 (m, 6H); ¹³C NMR(CDCl₃, 100 MHz): δ 194.20, 147.06, 146.32, 138.98, 136.41, 134.87,99.04, 64.42, 62.72, 30.53, 25.30, 19.66.

(E)-1-(tert-Butyl)-3-((5-chloro-3-(((tetrahydro-2H-pyran-2-yl)oxy)methyl)pyridin-2-yl)methylene)-1H-pyrrolo[2,3-b]pyridin-2(3H)-one(55)

To a solution of crude 53 (6.2 g, 68 wt %, 16.6 mmol) and 54 (3.46 g,18.3 mmol) in isopropanol (40 mL) was added DBU (0.12 g, 0.83 mmol) at−2° C. After stirring at −2° C. for 2 h, the solution was warmed up to10° C. and stirred at this temperature for 3 h. The yellow solidsprecipitated from the solution. The suspension was stirred over nightwhile the batch was allowed to warm up to room temperature slowly. Thesuspension was finally warm up to 50° C. and stirred for 4 h at thistemperature. After cooling to 30° C., water (35 ml) was added dropwiseover 30 min from an additional funnel. The suspension was cooled to roomtemperature and filtered. The cake was washed with a mixture ofisopropanol (3 mL) and water (3 mL). The precipitates were collected anddried in a vacuum oven over night at 50° C. to give 55 (6.2 g, 87%) as asolid. ¹H NMR (CDCl₃, 400 MHz): δ 8.72 (dd, J=7.5, 1.8 Hz), 8.66 (d,J=2.4 Hz, 1H), 8.18 (dd, J=5.1, 1.8 Hz, 1H), 7.94 (d, J=2.4 Hz, 1H),7.78 (s, 1H, 1H), 6.89 (dd, J=7.5, 5.1 Hz, 1H), 4.99 (d, J=13.8 Hz, 1H),4.80 (m, 1H), 4.70 (d, J=13.8 Hz, 1H), 3.90 (m, 1H), 3.60 (m, 1H), 1.83(s, 9H), 2.0-1.5 (m, 6H). The conformation of the double bond as transisomer was confirmed by NOE experiment. ¹³C NMR (CDCl₃, 100 MHz): δ168.75, 159.64, 148.99, 147.85, 146.65, 137.01, 135.29, 133.56, 132.41,129.50, 129.37, 117.27, 116.32, 98.77 64.80, 62.49, 58.62, 30.39, 29.01,25.26, 19.34.

1-(tert-Butyl)-3-((5-chloro-3-(hydroxymethyl)pyridin-2-yl)methyl)-1H-pyrrolo[2,3-b]pyridin-2(3H)-one(56)

To a suspension of 55 (3.0 g, 7.0 mmol) in ethanol (25 mL) was addedNaBH₄ (0.37 g) in one portion. The resulting suspension was stirred atroom temperature for 1 h. The reaction was quenched by adding water (10mL) followed by 6 N HCl solution in isopropanol (5 mL) slowly. Thesolution was warmed up to 40° C. and stirred for 3 h. The reactionmixture was mixed with MTBE (50 mL) and saturated aqueous NaCl (50 mL).The organic was separated and washed with water (50 mL). The solutionwas concentrated under vacuum at 50° C. and residue was triturated withhexane (30 mL). The resulting suspension was stirred at room temperaturefor 30 min. The precipitates were collected by filtration to give 56(2.2 g, 86%) as a solid. ¹H NMR (CDCl₃, 400 MHz): δ 8.34 (s, 1H), 8.15(d, J=4.9 Hz, 1H), 7.74 (s, 1H), 7.30 (d, J=7.1 Hz, 1H), 6.83 (t, J=5.7Hz, 1H), 4.73 (dd, J=13.4, 4.9 Hz, 1H), 4.63 (dd, J=13.4, 5.7 Hz, 1H),4.01 (t, J=6.1 Hz, 1H), 3.44 (dd, J=15.4, 5.2 Hz, 1H), 3.17 (dd, J=15.4,7.2 Hz, 1H), 2.94 (t, J=5.5 Hz, 1H), 1.79 (s, 9H); ¹³C NMR (CDCl₃, 100MHz): δ 178.72, 159.12, 153.82, 146.45, 145.83 135.72, 135.32, 130.63,130.27, 124.04, 117.33, 61.40, 58.70, 44.12, 34.01, 28.81.

1-(tert-Butyl)-3-((5-chloro-3-(chloromethyl)pyridin-2-yl)methyl)-1H-pyrrolo[2,3-b]pyridin-2(3H)-one(57)

To a solution of 56 (5.8 g, 16.8 mmol) in dichloromethane (30 mL) wasadded DMF (60 μl) and thionyl chloride (2.2 g) at 5° C. The mixture wasstirred for 30 min at this temperature followed by addition of 5%aqueous NaCl (30 mL). The organic layer was separated and washed with 5%aqueous NaCl (30 mL). The solvent was removed and the residue wasdissolved in heptane (20 mL). The solution was stirred for 30 min andthe product was precipitated. The suspension was cooled to 0° C. andfiltered to give 57 (5.8 g, 93%) as a solid: ¹H NMR (CDCl₃, 400 MHz): δ8.36 (d, J=2.3 Hz, 1H), 8.13 (dd, J=5.1, 1.4 Hz, 1H), 7.65 (d, J=2.3 Hz,1H), 7.19 (om, 1H), 6.78 (dd, J=7.3, 5.2 Hz, 1H), 4.58 (m, 2H), 4.06 (m,1H), 3.66 (dd, J=16.3, 4.6 Hz, 1H), 3.32 (dd, J=16.3, 7.5 Hz, 1H), 1.75(s, 9H); ¹³C NMR (CDCl₃, 100 MHz): δ 178.06, 159.45, 154.58, 147.39,145.73, 136.87, 132.47, 130.42, 130.11, 123.77, 117.03, 58.51, 43.37,42.25, 33.69, 28.82.

(S)-1′-(tert-Butyl)-3-chloro-5,7-dihydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridin]-2′(1′H)-one(58)

A solution of 57 (2.39 g, 6.56 mmol) in toluene (50 mL) was cooled to−2.5° C. under nitrogen atmosphere. Compound 61 (17 mg, 0.020 mmol) wascharged, and the resulting solution was aged for about 15 min whilecooled to −3.3° C. A pre-cooled (−1° C.) aqueous NaOH (26.2 mL, 0.3 N)was charged in over 4 min below −0.6° C. The reaction was aged at −1.3°C. for 3 h. The reaction was quenched with water (10 ml). The organiclayer was washed with water (10 mL), concentrated, flushed with IPA togive crude product 58 (2.59 g, 94.4% ee, 83% wt by NMR against1,3,5-trimethoxybenzene as an internal standard).

The crude product was recrystallized from IPA and water, filtered anddried in an oven at 50° C. to give 58 (1.95 g, 95.7% wt, 99% ee, 87%yield) as a solid. ¹H NMR (CDCl₃, 400 MHz): δ 8.42 (s, 1H), 8.19 (d,J=5.2 Hz, 1H), 7.56 (s, 1H), 7.10 (d, J=7.3 Hz, 1H), 6.83 (dd, J=7.3,5.2 Hz, 1H), 3.60 (dd, J=24.9, 16.8 Hz, 2H), 3.09 (dd, J=28.6, 16.8 Hz,2H); ¹³C NMR (CDCl₃, 100 Hz): δ 179.43, 160.54, 157.82, 147.44, 146.54,135.80, 132.17, 130.62, 129.33, 128.36, 117.69, 58.83, 51.94, 44.35,41.57, 28.83.

(1S,2R,4S,5R)-1-(2-Bromo-5-methoxybenzyl)-2-((S)-(1-(2-bromo-5-methoxybenzyl)-6-methoxyquinolin-1-ium-4-yl)(hydroxy)methyl)-5-vinylquinuclidin-1-iumbromide (61)

A slurry of quinidine (62, 8.1 g, 23.7 mmol, containing ˜14%dihydroquinidine) and 2-bromo-5-methoxybenzylbromide (63, 16.59 g, 59.3mmol) in IPA (4.0 ml) and DMF (28.4 mL) was degassed by vacuum andflushed with N₂, then heated to 70° C. for 7 h. The reaction mixture wascooled to 22° C., this reaction solution was charged to AcOEt (320 ml)at 22° C. over 10 min while stirring. The resulting slurry was aged at22° C. for 1 to 2 h, filtered, rinsed with AcOEt (2×24 ml), then hexane(2×24 ml). The solid was dried under vacuum to give powder as a mixtureof bis-salts (bis-quinidine salt 61 and bis-dihydroquinidine salt).(Total 19.7 g, 94% yield). The authentic sample of 61 was purified bySFC (IC column, 20×250 mm, 60% MeOH/CO₂, 50 mL/min, 100 bar, 35° C., 220nm, sample concentration: 133 mg/mL in MeOH; desired peak: 3 to 4.5min). ¹H NMR (CDCl₃, 500 MHz): δ 9.34 (d, J=6.1 Hz, 1H), 8.46 (d, J=6.1Hz, 1H), 8.38 (d, J=9.7 Hz, 1H), 8.0 (dd, J=9.7, 2.1 Hz, 1H), 7.86 (s,1H), 7.79 (d, J=8.9 Hz, 1H), 7.74 (d, J=8.9 Hz, 1H), 7.60 (d, J=2.5 Hz,1H), 7.42 (d, J=2.3 Hz, 1H), 7.17 (dd, J=8.8, 2.8 Hz, 1H), 7.03 (dd,J=8.8, 2.7 Hz, 1H), 6.93 (s, 1H), 6.50 (d, J=2.4 Hz, 1H), 6.06 (m, 1H),5.24 (m, 3H), 4.95 (d, J=12.9 Hz, 1H), 4.37 (m, 1H), 4.23 (m, 4H), 4.12(m, 1H), 3.88 (s, 3H), 3.69 (s, 3H), 3.54 (m, 1H), 3.32 (s, 2H), 3.23(m, 1H), 2.71 (m, 1H), 2.51 (s, 2H), 2.33 (m, 1H), 1.94 (br, 1H), 1.83(br, 2H), 1.17 (br, 1H); ¹³C NMR (DMSO-d₆, 100 Hz): δ 159.45, 159.07,158.67, 156.12, 146.01, 137.08, 134.68, 134.30, 133.21, 132.98, 128.18,128.03, 127.45, 122.13, 121.89, 121.22, 118.08, 117.5, 117.07, 116.73,116.20, 115.81, 112.67, 105.09, 66.81, 65.51, 62.43, 56.75, 56.06,55.91, 55.52, 54.80, 36.84, 25.91, 23.10, 20.75.

(S)-1′-(tert-Butyl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxylicacid (59)

A mixture of 58 (5.0 g, 14.5 mmol), K₂CO₃ (5.01 g, 36.2 mmol), Pd(OAc)₂(33 mg, 0.145 mmol), 1,3-bis(dicyclohexylphosphino)propane (DCPP, 127mg, 0.290 mmol) and water (0.522 mL, 29.0 mmol) in NMP (32 mL) washeated at 120° C. under 30 psi of CO for 24 h. After cooling to roomtemperature, the resulting slurry was diluted with water (100 mL). ThepH was slowly adjusted to 3-4 with 2 N HCl. The slurry was aged at roomtemperature for 1 h, filtered, rinsed with water (40 to 50 mL), driedunder oven at 60° C. to give 59 (4.64 g, 95%) as a solid. ¹H NMR(DMSO-d₆, 500 MHz): δ 8.90 (s, 1H), 8.19 (d, J=5.2 Hz, 1H), 7.54 (d,J=7.3 Hz, 1H,), 6.99 (dd, J=7.3, 5.2 Hz, 1H), 3.33 (m, 4H), 1.72 (s,9H); ¹³C NMR (DMSO-d₆, 125 MHz): δ 180.16, 167.44, 166.97, 158.07,149.76, 146.61, 135.39, 133.09, 130.36, 128.81, 125.48, 118.44, 58.19,51.12, 44.56, 41.24, 28.91.

(S)-2′-Oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxylicacid (14)

To 59 (4 g, 97% wt) was charged 37% HCl (40 to 44 mL). The slurry washeated at 94° C. for up to 48 h, cooled down to room temperature. Thesolvent was partially removed by reducing pressure to about total 2 vol(˜4 mL water remained). The residue was diluted with water (20 mL)followed by adjusting pH to 2.6 with NaOH (3.5 N, 4.5 mL). The thickslurry was aged for 1 to 2 h, filtered, rinsed with water (2×8 mL),followed by water/acetone (1:1, 8 mL). The wet cake was dried to givecompound 14 (3.1 g, 98% wt, 94%) as crystals. ¹H NMR (DMSO-d₆, 500 MHz):δ 13.31 (br, 1H), 11.14 (s, 1H), 8.91 (s, 1H), 8.11 (m, 2H), 7.49 (dd,J=7.3, 1.3 Hz, 1H), 6.93 (dd, J=7.3, 5.3 Hz, 1H), 3.36 (m, 4H); ¹³C NMR(DMSO-d₆, 125 MHz): δ 181.06, 167.36, 166.95, 156.80, 149.79, 147.32,135.37, 133.19, 130.73, 128.88, 125.50, 118.46, 51.78, 44.12, 40.70.

Example 7 1-(tert-Butyl)-1H-pyrrolo[2,3-b]pyridin-2(3H)-one (54)

A mixture of compound 54a (10.0 g, 40.3 mmol), NaCl (2.9 g) and water (2mL) in DMSO (50 mL) was heated at 120° C. for 30 min. The mixture wascooled to 30° C. followed by addition of MTBE (200 mL) and water (50mL). The organic layer was separated and the aqueous layer extractedwith another MTBE (50 mL). Combined organic layer was washed three timeswith water (50 mL). Solvent removed under vacuum and the resulting solidwas dried in a vacuum oven at 30° C. to give 54 (7.0 g, 92%) as a solid.¹H NMR (CDCl₃, 400 MHz): δ 8.15 (dd, J=5.2, 1.4 Hz, 1H), 7.40 (dd,J=7.2, 1.4 Hz, 1H), 6.88 (dd, J=7.2, 5.2 Hz, 1H), 3.45 (s, 2H), 1.78 (s,9H); ¹³C NMR (CDCl₃, 100 MHz): δ 174.99, 160.06, 145.82, 130.80, 119.51,117.15, 58.53, 35.98, 28.80.

Example 8

Methyl 5-chloro-3-(((triisopropylsilyl)oxy)methyl)picolinate (64)

To a solution of 52 (15.0 g, 67.4 mmol) in dichloromethane (60 mL) wasadded triisopropylsilyl trifluoromethanesulfonate (29.0 g, 94 mmol). Thesolution was cooled to 5° C. and imidazole (12.0 g, 176 mmol) was addedin a few portions below 20° C. The reaction mixture was stirred at roomtemperature for 5 min and 5% brine (50 mL) was charged. The organiclayer was separated and solvent removed under vacuum at 50° C. Theresulting oil was dissolved in methanol (100 mL). The solution was keptunder CO (100 psi) at 60° C. for 18 h in the presence of 5 mol % ofPd(dppf)Cl₂. The solvent was removed and the residue was transferredonto silica gel (60 g) on a filter funnel. The mixture was rinsed with amixture of 10% ethyl acetate in hexane (400 mL). The resulting solutionwas concentrated to give crude 64 (29.2 g, 98% LCAP, 84% wt, 100% yield)as an oil, which was used directly in the next step without furtherpurification. ¹H NMR (CDCl₃, 400 MHz): δ 8.56 (d, J=2.4 Hz, 1H), 8.30(d, J=2.4 Hz, 1H), 5.23 (s, 2H), 4.01 (s, 3H), 1.25 (m, 3H), 1.12 (d,J=6.8 Hz, 18H).

5-Chloro-2-(chloromethyl)-3-(((triisopropylsilyl)oxy)methyl)pyridine(65)

To a solution of crude 64 (29.2 g, 84 wt %, 67.4 mmol) in methanol (120mL) was added NaBH₄ (11.6 g) portionwise over about 1 h at 5° C. Thereaction mixture was quenched with water (150 mL) and the mixture wasextracted with MTBE (150 mL). The organic solution was washed with water(100 mL). The solvent was removed under vacuum at 50° C. and the residuewas dissolved in dichloromethane (60 mL). The solution was concentratedunder vacuum at 60° C. The resulting residue was dissolved indichloromethane (100 mL). The solution was cooled to 0° C. and DMF (0.5g) was added followed by thionyl chloride (11.1 g) dropwise. Thereaction mixture was then stirred for 30 min at 0° C. and quenched with5% brine (100 mL). The organic layer was separated and washed with brine(100 mL). Solvent was removed under vacuum at 60° C. to give 65 as anoil (25 g, 92% LCAP, 70% wt, 72% yield), which was used in the next stepwithout further purification. ¹H NMR (CDCl₃, 400 MHz): δ 8.44 (d, J=2.4Hz, 1H), 7.94 (d, J=2.4 Hz, 1H), 4.96 (s, 2H), 4.65 (s, 2H), 1.22 (m,3H), 1.12 (d, J=6.7 Hz, 18H).

1-(tert-Butyl)-3-((5-chloro-3-(hydroxymethyl)pyridin-2-yl)methyl)-1H-pyrrolo[2,3-b]pyridin-2(3H)-one(56)

To a solution of 65 (8 g, 70% wt, 16.1 mmol) and 54a (4.15 g) of in DMF(30 mL) was added Cs₂CO₃ (5.76 g) and NaI (2.4 g). The mixture wasstirred at room temperature for 1 h and the reaction mixture was mixedwith MTBE (100 mL) and 15% aqueous citric acid (80 mL). The organic waswashed with water (80 mL) twice and the solvent was removed. The residue(66, 90% LCAP) was dissolved in a mixture of ethanol (70 mL) and water(20 mL). After addition of LiOH (2.8 g), the solution was stirred for 30min at room temperature. The reaction mixture was acidified with 6N HClsolution in IPA (17 mL). The resulting solution was heated at 80° C. for2 h. After cooling to room temperature, the mixture was diluted withMTBE (100 mL) and 5% brine (50 mL). The organic layer was washed withwater (50 mL) and dried over MgSO₄. The solution was concentrated undervacuum at 50° C. and residue crystallized from hexane (30 mL), to give56 (3.75 g, 67% from 65) as crystals.

Example 9

Methyl tert-butyl(3-methylpyridin-2-yl)carbamate (68)

To N-(tert-butyl)-3-methylpyridin-2-amine (67) (16.78 g, 92% wt, 102mmol) in THF (100 ml) was addition MeMgCl (44.3 mL, 3M, 133 mmol) in THFunder −10° C. over 5 min. The reaction mixture was warmed up to roomtemperature and aged for 80 min, then cooled to −20 to −15° C. andmethyl chloroformate (8.7 ml, 112 mol) was added over 10 min under −8°C. The reaction mixture was gradually warmed up and aged overnight atroom temperature. The reaction mixture was quenched by addition of 15%aqueous citric acid (13 mL), water (40 mL) and MTBE (33 mL) at 0° C. Theorganic layer was separated and washed with water (50 mL), saturatedNaHCO₃/water (1:3, 50 ml), brine (50 mL) and water (50 mL), in turns.The organic layer was concentrated and flushed with THF to give 68 (19.3g, 92%).

1-(tert-Butyl)-1H-pyrrolo[2,3-b]pyridin-2(3H)-one hydrochloride (54b)

Compound 68 (5 g, 97% wt, 21.8 mmol) in THF (30 ml) or toluene (50 ml)was degassed, cooled to −45° C. LDA (45.8 mL, 1.0 N) was added between−45 to −40° C. over 13 min. (Note: LDA was prepared separately inanother flask by using 1.0 equiv n-BuLi and 1.1 equiv diisopropylaminein THF at −35° C. to 0 to 12° C., then cooled to 0° C.) The abovereaction mixture was gradually warmed up to 13° C. over 4.5 h, cooledunder an ice bath, and quenched with 2N HCl (˜40 mL) (pH-4) and toluene(15 mL) below 20° C. The organic layer was separated and washed water(15 mL), brine (15 mL), and water (15 mL), in turns. The organicsolution contained 54 (3.79 g, 91% assay yield) was concentrated,flushed with toluene to remove water. To a solution of the residue intoluene (7.6 mL), 2N HCl in ether (12 mL) was added over 30 min. To themixture was added hexane (8 ml) and aged 1 h. The precipitates werefiltered, rinsed toluene/hexane (1:2, 8 mL), then hexane (8 mL), anddried under vacuum with nitrogen stream to give salt 54b (3.92 g, 87%)as a solid. ¹H NMR (CDCl₃, 400 MHz): δ 11.9 (br, 1H), 8.13 (dd, J=5.2,0.8 Hz, 1H), 7.54 (dd, J=7.2, 1.1 Hz, 1H), 6.96 (dd, J=7.2, 5.2 Hz, 1H),3.52 (s, 2H), 1.69 (s, 9H); ¹³C NMR (DMSO-d₆, 100 MHz): δ 174.99, 159.8,145.67, 131.77, 120.54, 117.68, 57.89, 35.80, 28.99.

Example 10

1-(tert-Butyl)-3-((5-chloro-3-(((triisopropylsilyl)oxy)methyl)pyridin-2-yl)methyl)-1H-pyrrolo[2,3-b]pyridin-2(3H)-one(69)

A solution of 65 (23.84 g, 60.7 mmol) and 54 (17.32 g, 91 mmol) in THF(200 ml) was degassed by vacuum/flush N₂ below 5° C. To the solution wasadded lithium amoxide solution in heptanes (27.4 mL, 40%, 85 mmol)maintaining below 7° C. The reaction was aged below 5° C. for 40 min,then quenched with saturated aqueous NH₄Cl (10 mL), diluted with hexane(120 mL). The organic layer was separated, washed with saturated aqueousNH₄Cl (100 mL) and water (150 mL), concentrated and purified by silicagel column (0 to 5% AcOEt/hexane) to obtain 69, which was used in thenext reaction without further purification. HRMS m/z cacld. forC₂₈H₄₁C1N₃O₂Si 502.2651 (M+H). found 502.2641

1-(tert-Butyl)-3-((5-chloro-3-(hydroxymethyl)pyridin-2-yl)methyl)-1H-pyrrolo[2,3-b]pyridin-2(3H)-one(56)

A solution of 69 (max 60.7 mmol) in THF (50 mL) obtained from theprevious step was degassed with vacuum/flush N₂, cooled below 5° C.followed by charged TBAF (79 ml, 1.0 N in THF). The reaction aged atroom temperature for 1 h 20 min, cooled below 10° C., quenched withwater (100 ml), and diluted with AcOEt (200 mL). Aqueous layer wasextracted with AcOEt (100 mL). The combined organic layer was dried withMgSO₄, filtered, concentrated and purified by silica gel column (50 to100% AcOEt/hexane) to give 56 (16.3 g, 78% from 65) as a solid.

Example 11(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidetrihydrate

1.4 g of amorphous(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidefreebase was slurried in 28 ml of 95:5 water: acetonitrile for 3 days,filtered and dried to yield ˜1.1 g of the trihydrate.

Example 12(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemethanol solvate

500 mg of(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidefreebase monohydrate were dissolved in ˜3.5 ml of MeOH and dissolved at50° C. The solution was cooled to room temperature and allowed to cooland yielding crystalline MK-8031 Methanol solvate after about an hour.

Example 13(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemethanol water solvate

500 mg of(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidefreebase monohydrate was slurried in 7:3 MeOH: water at room temperaturefor 3 days yielding crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidefreebase methanol-water mixed solvate.

Example 14(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamideacetonitrile water solvate

To a mixture of 598 g (0.99 mol) of(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidetrihydrate and 3.2 L of acetonitrile was added 0.8 L of water. Themixture was heated to 30° C. to dissolve all solids. The solution wascooled to 20° C. and 6 g of acetonitrile/water solvate seeds wasintroduced. After the mixture was stirred at 20° C. 30 minutes, 4 L ofwater was added slowly over 4 hours. During the addition of water solidsprecipitated as acetonitrile/water mixed solvate.

Example 15(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamideacetonitrile solvate

(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidetrihydrate was dissolved in acetonitrile until solution until materialgelled. White solids formed out of the gel and this was suspended inadditional acetonitrile and stirred overnight yielding crystallineacetonitrile solvate.

Example 16 Amorphous(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamide

Drying of(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamideacetonitrile-water solvate at 75° C. under vacuum for one hour yields anX-ray Amorphous Form.

Example 17(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamideacetonitrile solvate

(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemonohydrate was slurried in acetonitrile for 3 days yielding solids ofan acetonitrile solvate.

Example 18(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamideL-tartaric acid cocrystal

To suspension of 500 mg of(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidetrihydrate in 5 mL of acetonitrile was added 5 mL of water slowly. ˜2 mLof addition of water, it became homogeneous. 124 mg of L-tartaric acidwas added and sonicated followed by stirring for 3 hours. Crystallinematerials was filtered and dried overnight at 40° C. yieldingcrystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-5-phenyl-1-(2,2,2-trifluoroethyl)piperidine-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamideL-tartaric acid cocrystal form.

Example 19(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamideL-tartaric acid cocrystal

3 g of(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemonohydrate and 0.724 g of L-tartaric acid was slurried in 15 ml MIBKovernight yielding a thick suspension. 45 ml of additional MIBK wasadded and slurrying continued for another day. The solids were isolatedand dried for 3 days under flowing nitrogen purge yielding crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamideL-tartaric acid cocrystal form.

1-11. (canceled)
 12. Crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemonohydrate.
 13. Crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemonohydrate according to claim 12 having a DSC extrapolated onsetmelting temperature of about 144° C. and a DSC peak melting temperatureof about 175° C.
 14. Crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,6-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamidemonohydrate according to claim 12 having d-spacings determined by x-raypowder diffraction, Cu K alpha, of about 12.7, 8.9, 8.1, 7.4, 6.4, 5.2,4.9, 4.8 and 4.0 angstroms.
 15. Crystalline(S)—N-((3S,5S,6R)-6-methyl-2-oxo-1-(2,2,2-trifluoroethyl)-5-(2,3,5-trifluorophenyl)piperidin-3-yl)-2′-oxo-1′,2′,5,7-tetrahydrospiro[cyclopenta[b]pyridine-6,3′-pyrrolo[2,3-b]pyridine]-3-carboxamide.16. A compound selected from: